cmake-commands(7) CMake cmake-commands(7)
NAME
cmake-commands - CMake Language Command Reference
SCRIPTING COMMANDS
These commands are always available.
block
Added in version 3.25.
Evaluate a group of commands with a dedicated variable and/or policy
scope.
block([SCOPE_FOR [POLICIES] [VARIABLES] ] [PROPAGATE <var-name>...])
<commands>
endblock()
All commands between block() and the matching endblock() <#
command:endblock> are recorded without being invoked. Once the
endblock() <#command:endblock> is evaluated, the recorded list of
commands is invoked inside the requested scopes, then the scopes
created by the block() command are removed.
SCOPE_FOR
Specify which scopes must be created.
POLICIES
Create a new policy scope. This is equivalent to
cmake_policy(PUSH) <#push> with an automatic
cmake_policy(POP) <#pop> when leaving the block scope.
VARIABLES
Create a new variable scope.
If SCOPE_FOR is not specified, this is equivalent to:
block(SCOPE_FOR VARIABLES POLICIES)
PROPAGATE
When a variable scope is created by the block() command, this
option sets or unsets the specified variables in the parent
scope. This is equivalent to set(PARENT_SCOPE) <#command:set> or
unset(PARENT_SCOPE) <#command:unset> commands.
set(var1 "INIT1")
set(var2 "INIT2")
block(PROPAGATE var1 var2)
set(var1 "VALUE1")
unset(var2)
endblock()
# Now var1 holds VALUE1, and var2 is unset
This option is only allowed when a variable scope is created. An
error will be raised in the other cases.
When the block() is inside a foreach() <#command:foreach> or while() <#
command:while> command, the break() <#command:break> and continue() <#
command:continue> commands can be used inside the block.
while(TRUE)
block()
...
# the break() command will terminate the while() command
break()
endblock()
endwhile()
See Also
o endblock() <#command:endblock>
o return() <#command:return>
o cmake_policy() <#command:cmake_policy>
break
Break from an enclosing foreach or while loop.
break()
Breaks from an enclosing foreach() <#command:foreach> or while() <#
command:while> loop.
See also the continue() <#command:continue> command.
cmake_host_system_information
Query various host system information.
Synopsis
Query host system specific information
cmake_host_system_information(RESULT <variable> QUERY <key> ...)
Query Windows registry
cmake_host_system_information(RESULT <variable> QUERY WINDOWS_REGISTRY <key> ...)
Query host system specific information
cmake_host_system_information(RESULT <variable> QUERY <key> ...)
Queries system information of the host system on which cmake runs. One
or more <key> can be provided to select the information to be queried.
The list of queried values is stored in <variable>.
<key> can be one of the following values:
NUMBER_OF_LOGICAL_CORES
Number of logical cores
NUMBER_OF_PHYSICAL_CORES
Number of physical cores
HOSTNAME
Hostname
FQDN Fully qualified domain name
TOTAL_VIRTUAL_MEMORY
Total virtual memory in MiB [1]
AVAILABLE_VIRTUAL_MEMORY
Available virtual memory in MiB [1]
TOTAL_PHYSICAL_MEMORY
Total physical memory in MiB [1]
AVAILABLE_PHYSICAL_MEMORY
Available physical memory in MiB [1]
IS_64BIT
Added in version 3.10.
One if processor is 64Bit
HAS_FPU
Added in version 3.10.
One if processor has floating point unit
HAS_MMX
Added in version 3.10.
One if processor supports MMX instructions
HAS_MMX_PLUS
Added in version 3.10.
One if processor supports Ext. MMX instructions
HAS_SSE
Added in version 3.10.
One if processor supports SSE instructions
HAS_SSE2
Added in version 3.10.
One if processor supports SSE2 instructions
HAS_SSE_FP
Added in version 3.10.
One if processor supports SSE FP instructions
HAS_SSE_MMX
Added in version 3.10.
One if processor supports SSE MMX instructions
HAS_AMD_3DNOW
Added in version 3.10.
One if processor supports 3DNow instructions
HAS_AMD_3DNOW_PLUS
Added in version 3.10.
One if processor supports 3DNow+ instructions
HAS_IA64
Added in version 3.10.
One if IA64 processor emulating x86
HAS_SERIAL_NUMBER
Added in version 3.10.
One if processor has serial number
PROCESSOR_SERIAL_NUMBER
Added in version 3.10.
Processor serial number
PROCESSOR_NAME
Added in version 3.10.
Human readable processor name
PROCESSOR_DESCRIPTION
Added in version 3.10.
Human readable full processor description
OS_NAME
Added in version 3.10.
See CMAKE_HOST_SYSTEM_NAME <#variable:CMAKE_HOST_SYSTEM_NAME>
OS_RELEASE
Added in version 3.10.
The OS sub-type e.g. on Windows Professional
OS_VERSION
Added in version 3.10.
The OS build ID
OS_PLATFORM
Added in version 3.10.
See CMAKE_HOST_SYSTEM_PROCESSOR <#
variable:CMAKE_HOST_SYSTEM_PROCESSOR>
MSYSTEM_PREFIX
Added in version 3.28.
Available only on Windows hosts. In a MSYS or MinGW development
environment that sets the MSYSTEM environment variable, this is
its installation prefix. Otherwise, this is the empty string.
DISTRIB_INFO
Added in version 3.22.
Read /etc/os-release file and define the given <variable> into a
list of read variables
DISTRIB_<name>
Added in version 3.22.
Get the <name> variable (see man 5 os-release <https://www
.freedesktop.org/software/systemd/man/latest/os-release.html>)
if it exists in the /etc/os-release file
Example:
cmake_host_system_information(RESULT PRETTY_NAME QUERY DISTRIB_PRETTY_NAME)
message(STATUS "${PRETTY_NAME}")
cmake_host_system_information(RESULT DISTRO QUERY DISTRIB_INFO)
foreach(VAR IN LISTS DISTRO)
message(STATUS "${VAR}=`${${VAR}}`")
endforeach()
Output:
-- Ubuntu 20.04.2 LTS
-- DISTRO_BUG_REPORT_URL=`https://bugs.launchpad.net/ubuntu/`
-- DISTRO_HOME_URL=`https://www.ubuntu.com/`
-- DISTRO_ID=`ubuntu`
-- DISTRO_ID_LIKE=`debian`
-- DISTRO_NAME=`Ubuntu`
-- DISTRO_PRETTY_NAME=`Ubuntu 20.04.2 LTS`
-- DISTRO_PRIVACY_POLICY_URL=`https://www.ubuntu.com/legal/terms-and-policies/privacy-policy`
-- DISTRO_SUPPORT_URL=`https://help.ubuntu.com/`
-- DISTRO_UBUNTU_CODENAME=`focal`
-- DISTRO_VERSION=`20.04.2 LTS (Focal Fossa)`
-- DISTRO_VERSION_CODENAME=`focal`
-- DISTRO_VERSION_ID=`20.04`
If /etc/os-release file is not found, the command tries to gather OS
identification via fallback scripts. The fallback script can use
various distribution-specific files <http://linuxmafia.com/faq/Admin/
release-files.html> to collect OS identification data and map it into
man 5 os-release <https://www.freedesktop.org/software/systemd/man/
latest/os-release.html> variables.
Fallback Interface Variables
CMAKE_GET_OS_RELEASE_FALLBACK_SCRIPTS
In addition to the scripts shipped with CMake, a user may append
full paths to his script(s) to the this list. The script
filename has the following format: NNN-<name>.cmake, where NNN
is three digits used to apply collected scripts in a specific
order.
CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_<varname>
Variables collected by the user provided fallback script ought
to be assigned to CMake variables using this naming convention.
Example, the ID variable from the manual becomes
CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_ID.
CMAKE_GET_OS_RELEASE_FALLBACK_RESULT
The fallback script ought to store names of all assigned
CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_<varname> variables in this
list.
Example:
# Try to detect some old distribution
# See also
# - http://linuxmafia.com/faq/Admin/release-files.html
#
if(NOT EXISTS "${CMAKE_SYSROOT}/etc/foobar-release")
return()
endif()
# Get the first string only
file(
STRINGS "${CMAKE_SYSROOT}/etc/foobar-release" CMAKE_GET_OS_RELEASE_FALLBACK_CONTENT
LIMIT_COUNT 1
)
#
# Example:
#
# Foobar distribution release 1.2.3 (server)
#
if(CMAKE_GET_OS_RELEASE_FALLBACK_CONTENT MATCHES "Foobar distribution release ([0-9\.]+) .*")
set(CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_NAME Foobar)
set(CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_PRETTY_NAME "${CMAKE_GET_OS_RELEASE_FALLBACK_CONTENT}")
set(CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_ID foobar)
set(CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_VERSION ${CMAKE_MATCH_1})
set(CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_VERSION_ID ${CMAKE_MATCH_1})
list(
APPEND CMAKE_GET_OS_RELEASE_FALLBACK_RESULT
CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_NAME
CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_PRETTY_NAME
CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_ID
CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_VERSION
CMAKE_GET_OS_RELEASE_FALLBACK_RESULT_VERSION_ID
)
endif()
unset(CMAKE_GET_OS_RELEASE_FALLBACK_CONTENT)
FOOTNOTES
[1] One MiB (mebibyte) is equal to 1024x1024 bytes.
Query Windows registry
Added in version 3.24.
cmake_host_system_information(RESULT <variable>
QUERY WINDOWS_REGISTRY <key> [VALUE_NAMES|SUBKEYS|VALUE <name>]
[VIEW (64|32|64_32|32_64|HOST|TARGET|BOTH)]
[SEPARATOR <separator>]
[ERROR_VARIABLE <result>])
Performs query operations on local computer registry subkey. Returns a
list of subkeys or value names that are located under the specified
subkey in the registry or the data of the specified value name. The
result of the queried entity is stored in <variable>.
Note:
Querying registry for any other platforms than Windows, including
CYGWIN, will always returns an empty string and sets an error
message in the variable specified with sub-option ERROR_VARIABLE.
<key> specify the full path of a subkey on the local computer. The
<key> must include a valid root key. Valid root keys for the local
computer are:
o HKLM or HKEY_LOCAL_MACHINE
o HKCU or HKEY_CURRENT_USER
o HKCR or HKEY_CLASSES_ROOT
o HKU or HKEY_USERS
o HKCC or HKEY_CURRENT_CONFIG
And, optionally, the path to a subkey under the specified root key. The
path separator can be the slash or the backslash. <key> is not case
sensitive. For example:
cmake_host_system_information(RESULT result QUERY WINDOWS_REGISTRY "HKLM")
cmake_host_system_information(RESULT result QUERY WINDOWS_REGISTRY "HKLM/SOFTWARE/Kitware")
cmake_host_system_information(RESULT result QUERY WINDOWS_REGISTRY "HKCU\\SOFTWARE\\Kitware")
VALUE_NAMES
Request the list of value names defined under <key>. If a
default value is defined, it will be identified with the special
name (default).
SUBKEYS
Request the list of subkeys defined under <key>.
VALUE <name>
Request the data stored in value named <name>. If VALUE is not
specified or argument is the special name (default), the content
of the default value, if any, will be returned.
# query default value for HKLM/SOFTWARE/Kitware key
cmake_host_system_information(RESULT result
QUERY WINDOWS_REGISTRY "HKLM/SOFTWARE/Kitware")
# query default value for HKLM/SOFTWARE/Kitware key using special value name
cmake_host_system_information(RESULT result
QUERY WINDOWS_REGISTRY "HKLM/SOFTWARE/Kitware"
VALUE "(default)")
Supported types are:
o REG_SZ.
o REG_EXPAND_SZ. The returned data is expanded.
o REG_MULTI_SZ. The returned is expressed as a CMake list. See
also SEPARATOR sub-option.
o REG_DWORD.
o REG_QWORD.
For all other types, an empty string is returned.
VIEW Specify which registry views must be queried. When not
specified, BOTH view is used.
64 Query the 64bit registry. On 32bit Windows, returns
always an empty string.
32 Query the 32bit registry.
64_32 For VALUE sub-option or default value, query the registry
using view 64, and if the request failed, query the
registry using view 32. For VALUE_NAMES and SUBKEYS
sub-options, query both views (64 and 32) and merge the
results (sorted and duplicates removed).
32_64 For VALUE sub-option or default value, query the registry
using view 32, and if the request failed, query the
registry using view 64. For VALUE_NAMES and SUBKEYS
sub-options, query both views (32 and 64) and merge the
results (sorted and duplicates removed).
HOST Query the registry matching the architecture of the host:
64 on 64bit Windows and 32 on 32bit Windows.
TARGET Query the registry matching the architecture specified by
CMAKE_SIZEOF_VOID_P <#variable:CMAKE_SIZEOF_VOID_P>
variable. If not defined, fallback to HOST view.
BOTH Query both views (32 and 64). The order depends of the
following rules: If CMAKE_SIZEOF_VOID_P <#
variable:CMAKE_SIZEOF_VOID_P> variable is defined. Use
the following view depending of the content of this
variable:
o 8: 64_32
o 4: 32_64
If CMAKE_SIZEOF_VOID_P <#variable:CMAKE_SIZEOF_VOID_P>
variable is not defined, rely on architecture of the
host:
o 64bit: 64_32
o 32bit: 32
SEPARATOR
Specify the separator character for REG_MULTI_SZ type. When not
specified, the character \0 is used.
ERROR_VARIABLE <result>
Returns any error raised during query operation. In case of
success, the variable holds an empty string.
cmake_language
Added in version 3.18.
Call meta-operations on CMake commands.
Synopsis
cmake_language(CALL <command> [<arg>...])
cmake_language(EVAL CODE <code>...)
cmake_language(DEFER <options>... CALL <command> [<arg>...])
cmake_language(SET_DEPENDENCY_PROVIDER <command> SUPPORTED_METHODS <methods>...)
cmake_language(GET_MESSAGE_LOG_LEVEL <out-var>)
cmake_language(EXIT <exit-code>)
Introduction
This command will call meta-operations on built-in CMake commands or
those created via the macro() <#command:macro> or function() <#
command:function> commands.
cmake_language does not introduce a new variable or policy scope.
Calling Commands
cmake_language(CALL <command> [<arg>...])
Calls the named <command> with the given arguments (if any).
For example, the code:
set(message_command "message")
cmake_language(CALL ${message_command} STATUS "Hello World!")
is equivalent to
message(STATUS "Hello World!")
Note:
To ensure consistency of the code, the following commands are
not allowed:
o if / elseif / else / endif
o block / endblock
o while / endwhile
o foreach / endforeach
o function / endfunction
o macro / endmacro
Evaluating Code
cmake_language(EVAL CODE <code>...)
Evaluates the <code>... as CMake code.
For example, the code:
set(A TRUE)
set(B TRUE)
set(C TRUE)
set(condition "(A AND B) OR C")
cmake_language(EVAL CODE "
if (${condition})
message(STATUS TRUE)
else()
message(STATUS FALSE)
endif()"
)
is equivalent to
set(A TRUE)
set(B TRUE)
set(C TRUE)
set(condition "(A AND B) OR C")
file(WRITE ${CMAKE_CURRENT_BINARY_DIR}/eval.cmake "
if (${condition})
message(STATUS TRUE)
else()
message(STATUS FALSE)
endif()"
)
include(${CMAKE_CURRENT_BINARY_DIR}/eval.cmake)
Deferring Calls
Added in version 3.19.
cmake_language(DEFER <options>... CALL <command> [<arg>...])
Schedules a call to the named <command> with the given arguments
(if any) to occur at a later time. By default, deferred calls
are executed as if written at the end of the current directory's
CMakeLists.txt file, except that they run even after a return()
<#command:return> call. Variable references in arguments are
evaluated at the time the deferred call is executed.
The options are:
DIRECTORY <dir>
Schedule the call for the end of the given directory
instead of the current directory. The <dir> may
reference either a source directory or its corresponding
binary directory. Relative paths are treated as relative
to the current source directory.
The given directory must be known to CMake, being either
the top-level directory or one added by
add_subdirectory() <#command:add_subdirectory>.
Furthermore, the given directory must not yet be finished
processing. This means it can be the current directory
or one of its ancestors.
ID <id>
Specify an identification for the deferred call. The
<id> may not be empty and may not begin with a capital
letter A-Z. The <id> may begin with an underscore (_)
only if it was generated automatically by an earlier call
that used ID_VAR to get the id.
ID_VAR <var>
Specify a variable in which to store the identification
for the deferred call. If ID <id> is not given, a new
identification will be generated and the generated id
will start with an underscore (_).
The currently scheduled list of deferred calls may be retrieved:
cmake_language(DEFER [DIRECTORY <dir>] GET_CALL_IDS <var>)
This will store in <var> a semicolon-separated list <#cmake-
language-lists> of deferred call ids. The ids are for the
directory scope in which the calls have been deferred to (i.e.
where they will be executed), which can be different to the
scope in which they were created. The DIRECTORY option can be
used to specify the scope for which to retrieve the call ids.
If that option is not given, the call ids for the current
directory scope will be returned.
Details of a specific call may be retrieved from its id:
cmake_language(DEFER [DIRECTORY <dir>] GET_CALL <id> <var>)
This will store in <var> a semicolon-separated list <#cmake-
language-lists> in which the first element is the name of the
command to be called, and the remaining elements are its
unevaluated arguments (any contained ; characters are included
literally and cannot be distinguished from multiple arguments).
If multiple calls are scheduled with the same id, this retrieves
the first one. If no call is scheduled with the given id in the
specified DIRECTORY scope (or the current directory scope if no
DIRECTORY option is given), this stores an empty string in the
variable.
Deferred calls may be canceled by their id:
cmake_language(DEFER [DIRECTORY <dir>] CANCEL_CALL <id>...)
This cancels all deferred calls matching any of the given ids in
the specified DIRECTORY scope (or the current directory scope if
no DIRECTORY option is given). Unknown ids are silently
ignored.
Deferred Call Examples
For example, the code:
cmake_language(DEFER CALL message "${deferred_message}")
cmake_language(DEFER ID_VAR id CALL message "Canceled Message")
cmake_language(DEFER CANCEL_CALL ${id})
message("Immediate Message")
set(deferred_message "Deferred Message")
prints:
Immediate Message
Deferred Message
The Canceled Message is never printed because its command is canceled.
The deferred_message variable reference is not evaluated until the call
site, so it can be set after the deferred call is scheduled.
In order to evaluate variable references immediately when scheduling a
deferred call, wrap it using cmake_language(EVAL). However, note that
arguments will be re-evaluated in the deferred call, though that can be
avoided by using bracket arguments. For example:
set(deferred_message "Deferred Message 1")
set(re_evaluated [[${deferred_message}]])
cmake_language(EVAL CODE "
cmake_language(DEFER CALL message [[${deferred_message}]])
cmake_language(DEFER CALL message \"${re_evaluated}\")
")
message("Immediate Message")
set(deferred_message "Deferred Message 2")
also prints:
Immediate Message
Deferred Message 1
Deferred Message 2
Dependency Providers
Added in version 3.24.
Note:
A high-level introduction to this feature can be found in the Using
Dependencies Guide <#dependency-providers-overview>.
cmake_language(SET_DEPENDENCY_PROVIDER <command> SUPPORTED_METHODS
<methods>...)
When a call is made to find_package() <#command:find_package> or
FetchContent_MakeAvailable() <#
command:fetchcontent_makeavailable>, the call may be forwarded
to a dependency provider which then has the opportunity to
fulfill the request. If the request is for one of the <methods>
specified when the provider was set, CMake calls the provider's
<command> with a set of method-specific arguments. If the
provider does not fulfill the request, or if the provider
doesn't support the request's method, or no provider is set, the
built-in find_package() <#command:find_package> or
FetchContent_MakeAvailable() <#
command:fetchcontent_makeavailable> implementation is used to
fulfill the request in the usual way.
One or more of the following values can be specified for the
<methods> when setting the provider:
FIND_PACKAGE
The provider command accepts find_package() <#
command:find_package> requests.
FETCHCONTENT_MAKEAVAILABLE_SERIAL
The provider command accepts FetchContent_MakeAvailable()
<#command:fetchcontent_makeavailable> requests. It
expects each dependency to be fed to the provider command
one at a time, not the whole list in one go.
Only one provider can be set at any point in time. If a
provider is already set when
cmake_language(SET_DEPENDENCY_PROVIDER) is called, the new
provider replaces the previously set one. The specified
<command> must already exist when
cmake_language(SET_DEPENDENCY_PROVIDER) is called. As a special
case, providing an empty string for the <command> and no
<methods> will discard any previously set provider.
The dependency provider can only be set while processing one of
the files specified by the CMAKE_PROJECT_TOP_LEVEL_INCLUDES <#
variable:CMAKE_PROJECT_TOP_LEVEL_INCLUDES> variable. Thus,
dependency providers can only be set as part of the first call
to project() <#command:project>. Calling
cmake_language(SET_DEPENDENCY_PROVIDER) outside of that context
will result in an error.
Added in version 3.30: The
PROPAGATE_TOP_LEVEL_INCLUDES_TO_TRY_COMPILE <#
prop_gbl:PROPAGATE_TOP_LEVEL_INCLUDES_TO_TRY_COMPILE> global
property can be set if the dependency provider also wants to be
enabled in whole-project calls to try_compile() <#
command:try_compile>.
Note:
The choice of dependency provider should always be under the
user's control. As a convenience, a project may choose to
provide a file that users can list in their
CMAKE_PROJECT_TOP_LEVEL_INCLUDES <#
variable:CMAKE_PROJECT_TOP_LEVEL_INCLUDES> variable, but the
use of such a file should always be the user's choice.
Provider commands
Providers define a single <command> to accept requests. The name of
the command should be specific to that provider, not something overly
generic that another provider might also use. This enables users to
compose different providers in their own custom provider. The
recommended form is xxx_provide_dependency(), where xxx is the
provider-specific part (e.g. vcpkg_provide_dependency(),
conan_provide_dependency(), ourcompany_provide_dependency(), and so
on).
xxx_provide_dependency(<method> [<method-specific-args>...])
Because some methods expect certain variables to be set in the calling
scope, the provider command should typically be implemented as a macro
rather than a function. This ensures it does not introduce a new
variable scope.
The arguments CMake passes to the dependency provider depend on the
type of request. The first argument is always the method, and it will
only ever be one of the <methods> that was specified when setting the
provider.
FIND_PACKAGE
The <method-specific-args> will be everything passed to the
find_package() <#command:find_package> call that requested the
dependency. The first of these <method-specific-args> will
therefore always be the name of the dependency. Dependency
names are case-sensitive for this method because find_package()
<#command:find_package> treats them case-sensitively too.
If the provider command fulfills the request, it must set the
same variable that find_package() <#command:find_package>
expects to be set. For a dependency named depName, the provider
must set depName_FOUND to true if it fulfilled the request. If
the provider returns without setting this variable, CMake will
assume the request was not fulfilled and will fall back to the
built-in implementation.
If the provider needs to call the built-in find_package() <#
command:find_package> implementation as part of its processing,
it can do so by including the BYPASS_PROVIDER keyword as one of
the arguments.
FETCHCONTENT_MAKEAVAILABLE_SERIAL
The <method-specific-args> will be everything passed to the
FetchContent_Declare() <#command:fetchcontent_declare> call that
corresponds to the requested dependency, with the following
exceptions:
o If SOURCE_DIR or BINARY_DIR were not part of the original
declared arguments, they will be added with their default
values.
o If FETCHCONTENT_TRY_FIND_PACKAGE_MODE <#
variable:FETCHCONTENT_TRY_FIND_PACKAGE_MODE> is set to NEVER,
any FIND_PACKAGE_ARGS will be omitted.
o The OVERRIDE_FIND_PACKAGE keyword is always omitted.
The first of the <method-specific-args> will always be the name
of the dependency. Dependency names are case-insensitive for
this method because FetchContent <#module:FetchContent> also
treats them case-insensitively.
If the provider fulfills the request, it should call
FetchContent_SetPopulated() <#
command:fetchcontent_setpopulated>, passing the name of the
dependency as the first argument. The SOURCE_DIR and BINARY_DIR
arguments to that command should only be given if the provider
makes the dependency's source and build directories available in
exactly the same way as the built-in
FetchContent_MakeAvailable() <#
command:fetchcontent_makeavailable> command.
If the provider returns without calling
FetchContent_SetPopulated() <#command:fetchcontent_setpopulated>
for the named dependency, CMake will assume the request was not
fulfilled and will fall back to the built-in implementation.
Note that empty arguments may be significant for this method
(e.g. an empty string following a GIT_SUBMODULES keyword).
Therefore, if forwarding these arguments on to another command,
extra care must be taken to avoid such arguments being silently
dropped.
If FETCHCONTENT_SOURCE_DIR_<uppercaseDepName> is set, then the
dependency provider will never see requests for the <depName>
dependency for this method. When the user sets such a variable,
they are explicitly overriding where to get that dependency from
and are taking on the responsibility that their overriding
version meets any requirements for that dependency and is
compatible with whatever else in the project uses it. Depending
on the value of FETCHCONTENT_TRY_FIND_PACKAGE_MODE <#
variable:FETCHCONTENT_TRY_FIND_PACKAGE_MODE> and whether the
OVERRIDE_FIND_PACKAGE option was given to FetchContent_Declare()
<#command:fetchcontent_declare>, having
FETCHCONTENT_SOURCE_DIR_<uppercaseDepName> set may also prevent
the dependency provider from seeing requests for a
find_package(depName) call too.
Provider Examples
This first example only intercepts find_package() <#
command:find_package> calls. The provider command runs an external
tool which copies the relevant artifacts into a provider-specific
directory, if that tool knows about the dependency. It then relies on
the built-in implementation to then find those artifacts.
FetchContent_MakeAvailable() <#command:fetchcontent_makeavailable>
calls would not go through the provider.
mycomp_provider.cmake
# Always ensure we have the policy settings this provider expects
cmake_minimum_required(VERSION 3.24)
set(MYCOMP_PROVIDER_INSTALL_DIR ${CMAKE_BINARY_DIR}/mycomp_packages
CACHE PATH "The directory this provider installs packages to"
)
# Tell the built-in implementation to look in our area first, unless
# the find_package() call uses NO_..._PATH options to exclude it
list(APPEND CMAKE_MODULE_PATH ${MYCOMP_PROVIDER_INSTALL_DIR}/cmake)
list(APPEND CMAKE_PREFIX_PATH ${MYCOMP_PROVIDER_INSTALL_DIR})
macro(mycomp_provide_dependency method package_name)
execute_process(
COMMAND some_tool ${package_name} --installdir ${MYCOMP_PROVIDER_INSTALL_DIR}
COMMAND_ERROR_IS_FATAL ANY
)
endmacro()
cmake_language(
SET_DEPENDENCY_PROVIDER mycomp_provide_dependency
SUPPORTED_METHODS FIND_PACKAGE
)
The user would then typically use the above file like so:
cmake -DCMAKE_PROJECT_TOP_LEVEL_INCLUDES=/path/to/mycomp_provider.cmake ...
The next example demonstrates a provider that accepts both methods, but
only handles one specific dependency. It enforces providing Google
Test using FetchContent <#module:FetchContent>, but leaves all other
dependencies to be fulfilled by CMake's built-in implementation. It
accepts a few different names, which demonstrates one way of working
around projects that hard-code an unusual or undesirable way of adding
this particular dependency to the build. The example also demonstrates
how to use the list() <#command:list> command to preserve variables
that may be overwritten by a call to FetchContent_MakeAvailable() <#
command:fetchcontent_makeavailable>.
mycomp_provider.cmake
cmake_minimum_required(VERSION 3.24)
# Because we declare this very early, it will take precedence over any
# details the project might declare later for the same thing
include(FetchContent)
FetchContent_Declare(
googletest
GIT_REPOSITORY https://github.com/google/googletest.git
GIT_TAG e2239ee6043f73722e7aa812a459f54a28552929 # release-1.11.0
)
# Both FIND_PACKAGE and FETCHCONTENT_MAKEAVAILABLE_SERIAL methods provide
# the package or dependency name as the first method-specific argument.
macro(mycomp_provide_dependency method dep_name)
if("${dep_name}" MATCHES "^(gtest|googletest)$")
# Save our current command arguments in case we are called recursively
list(APPEND mycomp_provider_args ${method} ${dep_name})
# This will forward to the built-in FetchContent implementation,
# which detects a recursive call for the same thing and avoids calling
# the provider again if dep_name is the same as the current call.
FetchContent_MakeAvailable(googletest)
# Restore our command arguments
list(POP_BACK mycomp_provider_args dep_name method)
# Tell the caller we fulfilled the request
if("${method}" STREQUAL "FIND_PACKAGE")
# We need to set this if we got here from a find_package() call
# since we used a different method to fulfill the request.
# This example assumes projects only use the gtest targets,
# not any of the variables the FindGTest module may define.
set(${dep_name}_FOUND TRUE)
elseif(NOT "${dep_name}" STREQUAL "googletest")
# We used the same method, but were given a different name to the
# one we populated with. Tell the caller about the name it used.
FetchContent_SetPopulated(${dep_name}
SOURCE_DIR "${googletest_SOURCE_DIR}"
BINARY_DIR "${googletest_BINARY_DIR}"
)
endif()
endif()
endmacro()
cmake_language(
SET_DEPENDENCY_PROVIDER mycomp_provide_dependency
SUPPORTED_METHODS
FIND_PACKAGE
FETCHCONTENT_MAKEAVAILABLE_SERIAL
)
The final example demonstrates how to modify arguments to a
find_package() <#command:find_package> call. It forces all such calls
to have the QUIET keyword. It uses the BYPASS_PROVIDER keyword to
prevent calling the provider command recursively for the same
dependency.
mycomp_provider.cmake
cmake_minimum_required(VERSION 3.24)
macro(mycomp_provide_dependency method)
find_package(${ARGN} BYPASS_PROVIDER QUIET)
endmacro()
cmake_language(
SET_DEPENDENCY_PROVIDER mycomp_provide_dependency
SUPPORTED_METHODS FIND_PACKAGE
)
Getting current message log level
Added in version 3.25.
cmake_language(GET_MESSAGE_LOG_LEVEL <output_variable>)
Writes the current message() <#command:message> logging level
into the given <output_variable>.
See message() <#command:message> for the possible logging
levels.
The current message logging level can be set either using the
--log-level <#cmdoption-cmake-log-level> command line option of
the cmake(1) <#manual:cmake(1)> program or using the
CMAKE_MESSAGE_LOG_LEVEL <#variable:CMAKE_MESSAGE_LOG_LEVEL>
variable.
If both the command line option and the variable are set, the
command line option takes precedence. If neither are set, the
default logging level is returned.
Terminating Scripts
Added in version 3.29.
cmake_language(EXIT <exit-code>)
Terminate the current cmake -P <#cmdoption-cmake-P> script and
exit with <exit-code>.
This command works only in script mode <#script-processing-
mode>. If used outside of that context, it will cause a fatal
error.
The <exit-code> should be non-negative. If <exit-code> is
negative, then the behavior is unspecified (e.g., on Windows the
error code -1 becomes 0xffffffff, and on Linux it becomes 255).
Exit codes above 255 may not be supported by the underlying
shell or platform, and some shells may interpret values above
125 specially. Therefore, it is advisable to only specify an
<exit-code> in the range 0 to 125.
cmake_minimum_required
Require a minimum version of cmake.
cmake_minimum_required(VERSION <min>[...<policy_max>] [FATAL_ERROR])
Added in version 3.12: The optional <policy_max> version.
Sets the minimum required version of cmake for a project. Also updates
the policy settings as explained below.
<min> and the optional <policy_max> are each CMake versions of the form
major.minor[.patch[.tweak]], and the ... is literal.
If the running version of CMake is lower than the <min> required
version it will stop processing the project and report an error. The
optional <policy_max> version, if specified, must be at least the <min>
version and affects policy settings as described in Policy Settings.
If the running version of CMake is older than 3.12, the extra ... dots
will be seen as version component separators, resulting in the ...<max>
part being ignored and preserving the pre-3.12 behavior of basing
policies on <min>.
This command will set the value of the CMAKE_MINIMUM_REQUIRED_VERSION
<#variable:CMAKE_MINIMUM_REQUIRED_VERSION> variable to <min>.
The FATAL_ERROR option is accepted but ignored by CMake 2.6 and higher.
It should be specified so CMake versions 2.4 and lower fail with an
error instead of just a warning.
Note:
Call the cmake_minimum_required() command at the beginning of the
top-level CMakeLists.txt file even before calling the project() <#
command:project> command. It is important to establish version and
policy settings before invoking other commands whose behavior they
may affect. See also policy CMP0000 <#policy:CMP0000>.
Calling cmake_minimum_required() inside a function() <#
command:function> limits some effects to the function scope when
invoked. For example, the CMAKE_MINIMUM_REQUIRED_VERSION <#
variable:CMAKE_MINIMUM_REQUIRED_VERSION> variable won't be set in
the calling scope. Functions do not introduce their own policy
scope though, so policy settings of the caller will be affected (see
below). Due to this mix of things that do and do not affect the
calling scope, calling cmake_minimum_required() inside a function is
generally discouraged.
Policy Settings
The cmake_minimum_required(VERSION) command implicitly invokes the
cmake_policy(VERSION) <#version> command to specify that the current
project code is written for the given range of CMake versions. All
policies known to the running version of CMake and introduced in the
<min> (or <max>, if specified) version or earlier will be set to use
NEW behavior. All policies introduced in later versions will be unset.
This effectively requests behavior preferred as of a given CMake
version and tells newer CMake versions to warn about their new
policies.
When a <min> version higher than 2.4 is specified the command
implicitly invokes
cmake_policy(VERSION <min>[...<max>])
which sets CMake policies based on the range of versions specified.
When a <min> version 2.4 or lower is given the command implicitly
invokes
cmake_policy(VERSION 2.4[...<max>])
which enables compatibility features for CMake 2.4 and lower.
Changed in version 3.31: Compatibility with versions of CMake older
than 3.10 is deprecated. Calls to cmake_minimum_required(VERSION) or
cmake_policy(VERSION) <#version> that do not specify at least 3.10 as
their policy version (optionally via ...<max>) will produce a
deprecation warning in CMake 3.31 and above.
Changed in version 3.27: Compatibility with versions of CMake older
than 3.5 is deprecated. Calls to cmake_minimum_required(VERSION) or
cmake_policy(VERSION) <#version> that do not specify at least 3.5 as
their policy version (optionally via ...<max>) will produce a
deprecation warning in CMake 3.27 and above.
Changed in version 3.19: Compatibility with versions of CMake older
than 2.8.12 is deprecated. Calls to cmake_minimum_required(VERSION) or
cmake_policy(VERSION) <#version> that do not specify at least 2.8.12 as
their policy version (optionally via ...<max>) will produce a
deprecation warning in CMake 3.19 and above.
See Also
o cmake_policy() <#command:cmake_policy>
cmake_parse_arguments
Parse function or macro arguments.
cmake_parse_arguments(<prefix> <options> <one_value_keywords>
<multi_value_keywords> <args>...)
cmake_parse_arguments(PARSE_ARGV <N> <prefix> <options>
<one_value_keywords> <multi_value_keywords>)
Added in version 3.5: This command is implemented natively.
Previously, it has been defined in the module CMakeParseArguments <#
module:CMakeParseArguments>.
This command is for use in macros or functions. It processes the
arguments given to that macro or function, and defines a set of
variables which hold the values of the respective options.
The first signature reads arguments passed in the <args>.... This may
be used in either a macro() <#command:macro> or a function() <#
command:function>.
Added in version 3.7: The PARSE_ARGV signature is only for use in a
function() <#command:function> body. In this case, the arguments that
are parsed come from the ARGV# variables of the calling function. The
parsing starts with the <N>-th argument, where <N> is an unsigned
integer. This allows for the values to have special characters like ;
in them.
The <options> argument contains all options for the respective function
or macro. These are keywords that have no value following them, like
the OPTIONAL keyword of the install() <#command:install> command.
The <one_value_keywords> argument contains all keywords for this
function or macro which are followed by one value, like the DESTINATION
keyword of the install() <#command:install> command.
The <multi_value_keywords> argument contains all keywords for this
function or macro which can be followed by more than one value, like
the TARGETS or FILES keywords of the install() <#command:install>
command.
Changed in version 3.5: All keywords must be unique. Each keyword can
only be specified once in any of the <options>, <one_value_keywords>,
or <multi_value_keywords>. A warning will be emitted if uniqueness is
violated.
When done, cmake_parse_arguments will consider for each of the keywords
listed in <options>, <one_value_keywords>, and <multi_value_keywords>,
a variable composed of the given <prefix> followed by "_" and the name
of the respective keyword. For <one_value_keywords> and
<multi_value_keywords>, these variables will then hold the respective
value(s) from the argument list, or be undefined if the associated
keyword was not given (policy CMP0174 <#policy:CMP0174> can also affect
the behavior for <one_value_keywords>). For the <options> keywords,
these variables will always be defined, and they will be set to TRUE if
the keyword is present, or FALSE if it is not.
All remaining arguments are collected in a variable
<prefix>_UNPARSED_ARGUMENTS that will be undefined if all arguments
were recognized. This can be checked afterwards to see whether your
macro or function was called with unrecognized parameters.
Added in version 3.15: <one_value_keywords> and <multi_value_keywords>
that were given no values at all are collected in a variable
<prefix>_KEYWORDS_MISSING_VALUES that will be undefined if all keywords
received values. This can be checked to see if there were keywords
without any values given.
Changed in version 3.31: If a <one_value_keyword> is followed by an
empty string as its value, policy CMP0174 <#policy:CMP0174> controls
whether a corresponding <prefix>_<keyword> variable is defined or not.
Choose a <prefix> carefully to avoid clashing with existing variable
names. When used inside a function, it is usually suitable to use the
prefix arg. There is a very strong convention that all keywords are
fully uppercase, so this prefix results in variables of the form
arg_SOME_KEYWORD. This makes the code more readable, and it minimizes
the chance of clashing with cache variables, which also have a strong
convention of being all uppercase.
function(my_install)
set(options OPTIONAL FAST)
set(oneValueArgs DESTINATION RENAME)
set(multiValueArgs TARGETS CONFIGURATIONS)
cmake_parse_arguments(PARSE_ARGV 0 arg
"${options}" "${oneValueArgs}" "${multiValueArgs}"
)
# The above will set or unset variables with the following names:
# arg_OPTIONAL
# arg_FAST
# arg_DESTINATION
# arg_RENAME
# arg_TARGETS
# arg_CONFIGURATIONS
#
# The following will also be set or unset:
# arg_UNPARSED_ARGUMENTS
# arg_KEYWORDS_MISSING_VALUES
When used inside a macro, arg might not be a suitable prefix because
the code will affect the calling scope. If another macro also called
in the same scope were to use arg in its own call to
cmake_parse_arguments(), and if there are any common keywords between
the two macros, the later call's variables can overwrite or remove
those of the earlier macro's call. Therefore, it is advisable to
incorporate something unique from the macro name in the <prefix>, such
as arg_lowercase_macro_name.
macro(my_install)
set(options OPTIONAL FAST)
set(oneValueArgs DESTINATION RENAME)
set(multiValueArgs TARGETS CONFIGURATIONS)
cmake_parse_arguments(arg_my_install
"${options}" "${oneValueArgs}" "${multiValueArgs}"
${ARGN}
)
# ...
endmacro()
macro(my_special_install)
# NOTE: Has the same keywords as my_install()
set(options OPTIONAL FAST)
set(oneValueArgs DESTINATION RENAME)
set(multiValueArgs TARGETS CONFIGURATIONS)
cmake_parse_arguments(arg_my_special_install
"${options}" "${oneValueArgs}" "${multiValueArgs}"
${ARGN}
)
# ...
endmacro()
Suppose the above macros are called one after the other, like so:
my_install(TARGETS foo bar DESTINATION bin OPTIONAL blub CONFIGURATIONS)
my_special_install(TARGETS barry DESTINATION sbin RENAME FAST)
After these two calls, the following describes the variables that will
be set or unset:
arg_my_install_OPTIONAL = TRUE
arg_my_install_FAST = FALSE # was not present in call to my_install
arg_my_install_DESTINATION = "bin"
arg_my_install_RENAME <UNSET> # was not present
arg_my_install_TARGETS = "foo;bar"
arg_my_install_CONFIGURATIONS <UNSET> # was not present
arg_my_install_UNPARSED_ARGUMENTS = "blub" # nothing expected after "OPTIONAL"
arg_my_install_KEYWORDS_MISSING_VALUES = "CONFIGURATIONS" # value was missing
arg_my_special_install_OPTIONAL = FALSE # was not present
arg_my_special_install_FAST = TRUE
arg_my_special_install_DESTINATION = "sbin"
arg_my_special_install_RENAME <UNSET> # value was missing
arg_my_special_install_TARGETS = "barry"
arg_my_special_install_CONFIGURATIONS <UNSET> # was not present
arg_my_special_install_UNPARSED_ARGUMENTS <UNSET>
arg_my_special_install_KEYWORDS_MISSING_VALUES = "RENAME"
Keywords terminate lists of values. If a keyword is given directly
after a <one_value_keyword>, that preceding <one_value_keyword>
receives no value and the keyword is added to the
<prefix>_KEYWORDS_MISSING_VALUES variable. In the above example, the
call to my_special_install() contains the RENAME keyword immediately
followed by the FAST keyword. In this case, FAST terminates processing
of the RENAME keyword. arg_my_special_install_FAST is set to TRUE,
arg_my_special_install_RENAME is unset, and
arg_my_special_install_KEYWORDS_MISSING_VALUES contains the value
RENAME.
See Also
o function() <#command:function>
o macro() <#command:macro>
cmake_path
Added in version 3.20.
This command is for the manipulation of paths. Only syntactic aspects
of paths are handled, there is no interaction of any kind with any
underlying file system. The path may represent a non-existing path or
even one that is not allowed to exist on the current file system or
platform. For operations that do interact with the filesystem, see the
file() <#command:file> command.
Note:
The cmake_path command handles paths in the format of the build
system (i.e. the host platform), not the target system. When
cross-compiling, if the path contains elements that are not
representable on the host platform (e.g. a drive letter when the
host is not Windows), the results will be unpredictable.
Synopsis
Conventions
Path Structure And Terminology
Normalization
Decomposition
cmake_path(GET <path-var> ROOT_NAME <out-var>)
cmake_path(GET <path-var> ROOT_DIRECTORY <out-var>)
cmake_path(GET <path-var> ROOT_PATH <out-var>)
cmake_path(GET <path-var> FILENAME <out-var>)
cmake_path(GET <path-var> EXTENSION [LAST_ONLY] <out-var>)
cmake_path(GET <path-var> STEM [LAST_ONLY] <out-var>)
cmake_path(GET <path-var> RELATIVE_PART <out-var>)
cmake_path(GET <path-var> PARENT_PATH <out-var>)
Query
cmake_path(HAS_ROOT_NAME <path-var> <out-var>)
cmake_path(HAS_ROOT_DIRECTORY <path-var> <out-var>)
cmake_path(HAS_ROOT_PATH <path-var> <out-var>)
cmake_path(HAS_FILENAME <path-var> <out-var>)
cmake_path(HAS_EXTENSION <path-var> <out-var>)
cmake_path(HAS_STEM <path-var> <out-var>)
cmake_path(HAS_RELATIVE_PART <path-var> <out-var>)
cmake_path(HAS_PARENT_PATH <path-var> <out-var>)
cmake_path(IS_ABSOLUTE <path-var> <out-var>)
cmake_path(IS_RELATIVE <path-var> <out-var>)
cmake_path(IS_PREFIX <path-var> <input> [NORMALIZE] <out-var>)
cmake_path(COMPARE <input1> <OP> <input2> <out-var>)
Modification
cmake_path(SET <path-var> [NORMALIZE] <input>)
cmake_path(APPEND <path-var> [<input>...] [OUTPUT_VARIABLE <out-var>])
cmake_path(APPEND_STRING <path-var> [<input>...] [OUTPUT_VARIABLE <out-var>])
cmake_path(REMOVE_FILENAME <path-var> [OUTPUT_VARIABLE <out-var>])
cmake_path(REPLACE_FILENAME <path-var> <input> [OUTPUT_VARIABLE <out-var>])
cmake_path(REMOVE_EXTENSION <path-var> [LAST_ONLY] [OUTPUT_VARIABLE <out-var>])
cmake_path(REPLACE_EXTENSION <path-var> [LAST_ONLY] <input> [OUTPUT_VARIABLE <out-var>])
Generation
cmake_path(NORMAL_PATH <path-var> [OUTPUT_VARIABLE <out-var>])
cmake_path(RELATIVE_PATH <path-var> [BASE_DIRECTORY <input>] [OUTPUT_VARIABLE <out-var>])
cmake_path(ABSOLUTE_PATH <path-var> [BASE_DIRECTORY <input>] [NORMALIZE] [OUTPUT_VARIABLE <out-var>])
Native Conversion
cmake_path(NATIVE_PATH <path-var> [NORMALIZE] <out-var>)
cmake_path(CONVERT <input> TO_CMAKE_PATH_LIST <out-var> [NORMALIZE])
cmake_path(CONVERT <input> TO_NATIVE_PATH_LIST <out-var> [NORMALIZE])
Hashing
cmake_path(HASH <path-var> <out-var>)
Conventions
The following conventions are used in this command's documentation:
<path-var>
Always the name of a variable. For commands that expect a
<path-var> as input, the variable must exist and it is expected
to hold a single path.
<input>
A string literal which may contain a path, path fragment, or
multiple paths with a special separator depending on the
command. See the description of each command to see how this is
interpreted.
<input>...
Zero or more string literal arguments.
<out-var>
The name of a variable into which the result of a command will
be written.
Path Structure And Terminology
A path has the following structure (all components are optional, with
some constraints):
root-name root-directory-separator (item-name directory-separator)* filename
root-name
Identifies the root on a filesystem with multiple roots (such as
"C:" or "//myserver"). It is optional.
root-directory-separator
A directory separator that, if present, indicates that this path
is absolute. If it is missing and the first element other than
the root-name is an item-name, then the path is relative.
item-name
A sequence of characters that aren't directory separators. This
name may identify a file, a hard link, a symbolic link, or a
directory. Two special cases are recognized:
o The item name consisting of a single dot character . is a
directory name that refers to the current directory.
o The item name consisting of two dot characters .. is a
directory name that refers to the parent directory.
The (...)* pattern shown above is to indicate that there can be
zero or more item names, with multiple items separated by a
directory-separator. The ()* characters are not part of the
path.
directory-separator
The only recognized directory separator is a forward slash
character /. If this character is repeated, it is treated as a
single directory separator. In other words, /usr///////lib is
the same as /usr/lib.
filename
A path has a filename if it does not end with a
directory-separator. The filename is effectively the last
item-name of the path, so it can also be a hard link, symbolic
link or a directory.
A filename can have an extension. By default, the extension is
defined as the sub-string beginning at the left-most period
(including the period) and until the end of the filename. In
commands that accept a LAST_ONLY keyword, LAST_ONLY changes the
interpretation to the sub-string beginning at the right-most
period.
The following exceptions apply to the above interpretation:
o If the first character in the filename is a period, that
period is ignored (i.e. a filename like ".profile" is
treated as having no extension).
o If the filename is either . or .., it has no extension.
The stem is the part of the filename before the extension.
Some commands refer to a root-path. This is the concatenation of
root-name and root-directory-separator, either or both of which can be
empty. A relative-part refers to the full path with any root-path
removed.
Creating A Path Variable
While a path can be created with care using an ordinary set() <#
command:set> command, it is recommended to use cmake_path(SET) instead,
as it automatically converts the path to the required form where
required. The cmake_path(APPEND) subcommand may be another suitable
alternative where a path needs to be constructed by joining fragments.
The following example compares the three methods for constructing the
same path:
set(path1 "${CMAKE_CURRENT_SOURCE_DIR}/data")
cmake_path(SET path2 "${CMAKE_CURRENT_SOURCE_DIR}/data")
cmake_path(APPEND path3 "${CMAKE_CURRENT_SOURCE_DIR}" "data")
Modification and Generation sub-commands can either store the result
in-place, or in a separate variable named after an OUTPUT_VARIABLE
keyword. All other sub-commands store the result in a mandatory
<out-var> variable.
Normalization
Some sub-commands support normalizing a path. The algorithm used to
normalize a path is as follows:
1. If the path is empty, stop (the normalized form of an empty path is
also an empty path).
2. Replace each directory-separator, which may consist of multiple
separators, with a single / (/a///b --> /a/b).
3. Remove each solitary period (.) and any immediately following
directory-separator (/a/./b/. --> /a/b).
4. Remove each item-name (other than ..) that is immediately followed
by a directory-separator and a .., along with any immediately
following directory-separator (/a/b/../c --> a/c).
5. If there is a root-directory, remove any .. and any
directory-separators immediately following them. The parent of the
root directory is treated as still the root directory (/../a -->
/a).
6. If the last item-name is .., remove any trailing directory-separator
(../ --> ..).
7. If the path is empty by this stage, add a dot (normal form of ./ is
.).
Decomposition
The following forms of the GET subcommand each retrieve a different
component or group of components from a path. See Path Structure And
Terminology for the meaning of each path component.
cmake_path(GET <path-var> ROOT_NAME <out-var>)
cmake_path(GET <path-var> ROOT_DIRECTORY <out-var>)
cmake_path(GET <path-var> ROOT_PATH <out-var>)
cmake_path(GET <path-var> FILENAME <out-var>)
cmake_path(GET <path-var> EXTENSION [LAST_ONLY] <out-var>)
cmake_path(GET <path-var> STEM [LAST_ONLY] <out-var>)
cmake_path(GET <path-var> RELATIVE_PART <out-var>)
cmake_path(GET <path-var> PARENT_PATH <out-var>)
If a requested component is not present in the path, an empty string
will be stored in <out-var>. For example, only Windows systems have
the concept of a root-name, so when the host machine is non-Windows,
the ROOT_NAME subcommand will always return an empty string.
For PARENT_PATH, if the HAS_RELATIVE_PART subcommand returns false, the
result is a copy of <path-var>. Note that this implies that a root
directory is considered to have a parent, with that parent being
itself. Where HAS_RELATIVE_PART returns true, the result will
essentially be <path-var> with one less element.
Root examples
set(path "c:/a")
cmake_path(GET path ROOT_NAME rootName)
cmake_path(GET path ROOT_DIRECTORY rootDir)
cmake_path(GET path ROOT_PATH rootPath)
message("Root name is \"${rootName}\"")
message("Root directory is \"${rootDir}\"")
message("Root path is \"${rootPath}\"")
Root name is "c:"
Root directory is "/"
Root path is "c:/"
Filename examples
set(path "/a/b")
cmake_path(GET path FILENAME filename)
message("First filename is \"${filename}\"")
# Trailing slash means filename is empty
set(path "/a/b/")
cmake_path(GET path FILENAME filename)
message("Second filename is \"${filename}\"")
First filename is "b"
Second filename is ""
Extension and stem examples
set(path "name.ext1.ext2")
cmake_path(GET path EXTENSION fullExt)
cmake_path(GET path STEM fullStem)
message("Full extension is \"${fullExt}\"")
message("Full stem is \"${fullStem}\"")
# Effect of LAST_ONLY
cmake_path(GET path EXTENSION LAST_ONLY lastExt)
cmake_path(GET path STEM LAST_ONLY lastStem)
message("Last extension is \"${lastExt}\"")
message("Last stem is \"${lastStem}\"")
# Special cases
set(dotPath "/a/.")
set(dotDotPath "/a/..")
set(someMorePath "/a/.some.more")
cmake_path(GET dotPath EXTENSION dotExt)
cmake_path(GET dotPath STEM dotStem)
cmake_path(GET dotDotPath EXTENSION dotDotExt)
cmake_path(GET dotDotPath STEM dotDotStem)
cmake_path(GET dotMorePath EXTENSION someMoreExt)
cmake_path(GET dotMorePath STEM someMoreStem)
message("Dot extension is \"${dotExt}\"")
message("Dot stem is \"${dotStem}\"")
message("Dot-dot extension is \"${dotDotExt}\"")
message("Dot-dot stem is \"${dotDotStem}\"")
message(".some.more extension is \"${someMoreExt}\"")
message(".some.more stem is \"${someMoreStem}\"")
Full extension is ".ext1.ext2"
Full stem is "name"
Last extension is ".ext2"
Last stem is "name.ext1"
Dot extension is ""
Dot stem is "."
Dot-dot extension is ""
Dot-dot stem is ".."
.some.more extension is ".more"
.some.more stem is ".some"
Relative part examples
set(path "c:/a/b")
cmake_path(GET path RELATIVE_PART result)
message("Relative part is \"${result}\"")
set(path "c/d")
cmake_path(GET path RELATIVE_PART result)
message("Relative part is \"${result}\"")
set(path "/")
cmake_path(GET path RELATIVE_PART result)
message("Relative part is \"${result}\"")
Relative part is "a/b"
Relative part is "c/d"
Relative part is ""
Path traversal examples
set(path "c:/a/b")
cmake_path(GET path PARENT_PATH result)
message("Parent path is \"${result}\"")
set(path "c:/")
cmake_path(GET path PARENT_PATH result)
message("Parent path is \"${result}\"")
Parent path is "c:/a"
Parent path is "c:/"
Query
Each of the GET subcommands has a corresponding HAS_... subcommand
which can be used to discover whether a particular path component is
present. See Path Structure And Terminology for the meaning of each
path component.
cmake_path(HAS_ROOT_NAME <path-var> <out-var>)
cmake_path(HAS_ROOT_DIRECTORY <path-var> <out-var>)
cmake_path(HAS_ROOT_PATH <path-var> <out-var>)
cmake_path(HAS_FILENAME <path-var> <out-var>)
cmake_path(HAS_EXTENSION <path-var> <out-var>)
cmake_path(HAS_STEM <path-var> <out-var>)
cmake_path(HAS_RELATIVE_PART <path-var> <out-var>)
cmake_path(HAS_PARENT_PATH <path-var> <out-var>)
Each of the above follows the predictable pattern of setting <out-var>
to true if the path has the associated component, or false otherwise.
Note the following special cases:
o For HAS_ROOT_PATH, a true result will only be returned if at least
one of root-name or root-directory is non-empty.
o For HAS_PARENT_PATH, the root directory is also considered to have a
parent, which will be itself. The result is true except if the path
consists of just a filename.
cmake_path(IS_ABSOLUTE <path-var> <out-var>)
Sets <out-var> to true if <path-var> is absolute. An absolute path is
a path that unambiguously identifies the location of a file without
reference to an additional starting location. On Windows, this means
the path must have both a root-name and a root-directory-separator to
be considered absolute. On other platforms, just a
root-directory-separator is sufficient. Note that this means on
Windows, IS_ABSOLUTE can be false while HAS_ROOT_DIRECTORY can be true.
cmake_path(IS_RELATIVE <path-var> <out-var>)
This will store the opposite of IS_ABSOLUTE in <out-var>.
cmake_path(IS_PREFIX <path-var> <input> [NORMALIZE] <out-var>)
Checks if <path-var> is the prefix of <input>.
When the NORMALIZE option is specified, <path-var> and <input> are
normalized before the check.
set(path "/a/b/c")
cmake_path(IS_PREFIX path "/a/b/c/d" result) # result = true
cmake_path(IS_PREFIX path "/a/b" result) # result = false
cmake_path(IS_PREFIX path "/x/y/z" result) # result = false
set(path "/a/b")
cmake_path(IS_PREFIX path "/a/c/../b" NORMALIZE result) # result = true
cmake_path(COMPARE <input1> EQUAL <input2> <out-var>)
cmake_path(COMPARE <input1> NOT_EQUAL <input2> <out-var>)
Compares the lexical representations of two paths provided as string
literals. No normalization is performed on either path, except
multiple consecutive directory separators are effectively collapsed
into a single separator. Equality is determined according to the
following pseudo-code logic:
if(NOT <input1>.root_name() STREQUAL <input2>.root_name())
return FALSE
if(<input1>.has_root_directory() XOR <input2>.has_root_directory())
return FALSE
Return FALSE if a relative portion of <input1> is not lexicographically
equal to the relative portion of <input2>. This comparison is performed path
component-wise. If all of the components compare equal, then return TRUE.
Note:
Unlike most other cmake_path() subcommands, the COMPARE subcommand
takes literal strings as input, not the names of variables.
Modification
cmake_path(SET <path-var> [NORMALIZE] <input>)
Assign the <input> path to <path-var>. If <input> is a native path, it
is converted into a cmake-style path with forward-slashes (/). On
Windows, the long filename marker is taken into account.
When the NORMALIZE option is specified, the path is normalized after
the conversion.
For example:
set(native_path "c:\\a\\b/..\\c")
cmake_path(SET path "${native_path}")
message("CMake path is \"${path}\"")
cmake_path(SET path NORMALIZE "${native_path}")
message("Normalized CMake path is \"${path}\"")
Output:
CMake path is "c:/a/b/../c"
Normalized CMake path is "c:/a/c"
cmake_path(APPEND <path-var> [<input>...] [OUTPUT_VARIABLE <out-var>])
Append all the <input> arguments to the <path-var> using / as the
directory-separator. Depending on the <input>, the previous contents
of <path-var> may be discarded. For each <input> argument, the
following algorithm (pseudo-code) applies:
# <path> is the contents of <path-var>
if(<input>.is_absolute() OR
(<input>.has_root_name() AND
NOT <input>.root_name() STREQUAL <path>.root_name()))
replace <path> with <input>
return()
endif()
if(<input>.has_root_directory())
remove any root-directory and the entire relative path from <path>
elseif(<path>.has_filename() OR
(NOT <path-var>.has_root_directory() OR <path>.is_absolute()))
append directory-separator to <path>
endif()
append <input> omitting any root-name to <path>
cmake_path(APPEND_STRING <path-var> [<input>...] [OUTPUT_VARIABLE <out-var>])
Append all the <input> arguments to the <path-var> without adding any
directory-separator.
cmake_path(REMOVE_FILENAME <path-var> [OUTPUT_VARIABLE <out-var>])
Removes the filename component (as returned by GET ... FILENAME) from
<path-var>. After removal, any trailing directory-separator is left
alone, if present.
If OUTPUT_VARIABLE is not given, then after this function returns,
HAS_FILENAME returns false for <path-var>.
For example:
set(path "/a/b")
cmake_path(REMOVE_FILENAME path)
message("First path is \"${path}\"")
# filename is now already empty, the following removes nothing
cmake_path(REMOVE_FILENAME path)
message("Second path is \"${path}\"")
Output:
First path is "/a/"
Second path is "/a/"
cmake_path(REPLACE_FILENAME <path-var> <input> [OUTPUT_VARIABLE <out-var>])
Replaces the filename component from <path-var> with <input>. If
<path-var> has no filename component (i.e. HAS_FILENAME returns
false), the path is unchanged. The operation is equivalent to the
following:
cmake_path(HAS_FILENAME path has_filename)
if(has_filename)
cmake_path(REMOVE_FILENAME path)
cmake_path(APPEND path input);
endif()
cmake_path(REMOVE_EXTENSION <path-var> [LAST_ONLY]
[OUTPUT_VARIABLE <out-var>])
Removes the extension, if any, from <path-var>.
cmake_path(REPLACE_EXTENSION <path-var> [LAST_ONLY] <input>
[OUTPUT_VARIABLE <out-var>])
Replaces the extension with <input>. Its effect is equivalent to the
following:
cmake_path(REMOVE_EXTENSION path)
if(NOT "input" MATCHES "^\\.")
cmake_path(APPEND_STRING path ".")
endif()
cmake_path(APPEND_STRING path "input")
Generation
cmake_path(NORMAL_PATH <path-var> [OUTPUT_VARIABLE <out-var>])
Normalize <path-var> according the steps described in Normalization.
cmake_path(RELATIVE_PATH <path-var> [BASE_DIRECTORY <input>]
[OUTPUT_VARIABLE <out-var>])
Modifies <path-var> to make it relative to the BASE_DIRECTORY argument.
If BASE_DIRECTORY is not specified, the default base directory will be
CMAKE_CURRENT_SOURCE_DIR <#variable:CMAKE_CURRENT_SOURCE_DIR>.
For reference, the algorithm used to compute the relative path is the
same as that used by C++ std::filesystem::path::lexically_relative
<https://en.cppreference.com/w/cpp/filesystem/path/lexically_normal>.
cmake_path(ABSOLUTE_PATH <path-var> [BASE_DIRECTORY <input>] [NORMALIZE]
[OUTPUT_VARIABLE <out-var>])
If <path-var> is a relative path (IS_RELATIVE is true), it is evaluated
relative to the given base directory specified by BASE_DIRECTORY
option. If BASE_DIRECTORY is not specified, the default base directory
will be CMAKE_CURRENT_SOURCE_DIR <#variable:CMAKE_CURRENT_SOURCE_DIR>.
When the NORMALIZE option is specified, the path is normalized after
the path computation.
Because cmake_path() does not access the filesystem, symbolic links are
not resolved and any leading tilde is not expanded. To compute a real
path with symbolic links resolved and leading tildes expanded, use the
file(REAL_PATH) <#real-path> command instead.
Native Conversion
For commands in this section, native refers to the host platform, not
the target platform when cross-compiling.
cmake_path(NATIVE_PATH <path-var> [NORMALIZE] <out-var>)
Converts a cmake-style <path-var> into a native path with
platform-specific slashes (\ on Windows hosts and / elsewhere).
When the NORMALIZE option is specified, the path is normalized before
the conversion.
cmake_path(CONVERT <input> TO_CMAKE_PATH_LIST <out-var> [NORMALIZE])
Converts a native <input> path into a cmake-style path with forward
slashes (/). On Windows hosts, the long filename marker is taken into
account. The input can be a single path or a system search path like
$ENV{PATH}. A search path will be converted to a cmake-style list
separated by ; characters (on non-Windows platforms, this essentially
means : separators are replaced with ;). The result of the conversion
is stored in the <out-var> variable.
When the NORMALIZE option is specified, the path is normalized before
the conversion.
Note:
Unlike most other cmake_path() subcommands, the CONVERT subcommand
takes a literal string as input, not the name of a variable.
cmake_path(CONVERT <input> TO_NATIVE_PATH_LIST <out-var> [NORMALIZE])
Converts a cmake-style <input> path into a native path with
platform-specific slashes (\ on Windows hosts and / elsewhere). The
input can be a single path or a cmake-style list. A list will be
converted into a native search path (;-separated on Windows,
:-separated on other platforms). The result of the conversion is
stored in the <out-var> variable.
When the NORMALIZE option is specified, the path is normalized before
the conversion.
Note:
Unlike most other cmake_path() subcommands, the CONVERT subcommand
takes a literal string as input, not the name of a variable.
For example:
set(paths "/a/b/c" "/x/y/z")
cmake_path(CONVERT "${paths}" TO_NATIVE_PATH_LIST native_paths)
message("Native path list is \"${native_paths}\"")
Output on Windows:
Native path list is "\a\b\c;\x\y\z"
Output on all other platforms:
Native path list is "/a/b/c:/x/y/z"
Hashing
cmake_path(HASH <path-var> <out-var>)
Compute a hash value of <path-var> such that for two paths p1 and p2
that compare equal (COMPARE ... EQUAL <#compare>), the hash value of p1
is equal to the hash value of p2. The path is always normalized before
the hash is computed.
cmake_pkg_config
Added in version 3.31.
Process pkg-config format package files.
Synopsis
cmake_pkg_config(EXTRACT <package> [<version>] [...])
Introduction
This command generates CMake variables and targets from pkg-config
format package files natively, without needing to invoke or even
require the presence of a pkg-config implementation. A <package> is
either an absolute path to a package file, or a package name to be
searched for using the typical pkg-config search patterns. The optional
<version> string has the same format and semantics as a pkg-config
style version specifier, with the exception that if no comparison
operator is specified = is assumed.
There are multiple signatures for this command, and some of the options
are common between them. They are:
EXACT / QUIET / REQUIRED
The EXACT option requests that the version string be matched
exactly (including empty string, if no version is provided),
overriding the typical pkg-config version comparison algorithm.
This will ignore any comparison operator attached to the version
string.
The QUIET option disables informational messages, including
those indicating that the package cannot be found if it is not
REQUIRED. The REQUIRED option stops processing with an error
message if the package cannot be found.
STRICTNESS <mode>
Specify how strictly the contents of the package files will be
verified during parsing and resolution. An invalid file, under
the provided strictness mode, will cause the command to fail.
Possible modes are:
o STRICT: Closely mirrors the behavior of the original FDO
pkg-config. Variables and keywords must be unique. Variables
must be defined before they are used. The Name, Description,
and Version keywords must be present. The overall structure
of the file must be valid and parsable.
o PERMISSIVE: Closely mirrors the behavior of the pkgconf
implementation. Duplicate variables are overridden. Duplicate
keywords are appended. Undefined variables resolve to empty
strings. The Name, Description, and Version keywords must be
present. The overall structure of the file must be valid and
parsable.
o BEST_EFFORT: Same behavior as PERMISSIVE with regards to
duplicate or uninitialized variables and keywords, but will
not fail under any conditions. Package files which require
BEST_EFFORT will fail validation under all other major
implementations and should be fixed.
The default strictness is PERMISSIVE.
ENV_MODE
Specifies which environment variables will be queried when
running a given command. Possible modes are:
o FDO: Queries only the original set of PKG_CONFIG_* environment
variables used by the freedesktop.org pkg-config
implementation.
o PKGCONF: Queries the more extensive set of environment
variables used by the pkgconf implementation.
o IGNORE: Ignores the presence, absence, and value of
environment variables entirely. In all cases an environment
variable would be queried its treated as defined, but with a
value of empty string for the purpose of the operation. This
does not modify the current environment. For boolean
environment variables, such as PKG_CONFIG_ALLOW_*, this means
they are evaluated as truthy.
PKG_CONFIG_SYSROOT_PATH is a minor exception. When ENV_MODE
IGNORE is used, no root path prepending will occur by default
and pc_sysrootdir remains defaulted to /.
Target-generating subcommands always ignore flag-filtering
environment variables. The default environment mode is PKGCONF.
PC_LIBDIR <path>...
Overrides the default search location for package files; also
used to derive the pc_path package variable.
When this option is not provided, the default library directory
is the first available of the following values:
1. CMAKE_PKG_CONFIG_PC_LIB_DIRS
2. The PKG_CONFIG_LIBDIR environment variable
3. The output of pkg-config --variable pc_path pkg-config
4. A platform-dependent default value
PC_PATH <path>...
Overrides the supplemental package file directories which will
be prepended to the search path; also used to derive the pc_path
package variable.
When this option is not provided, the default paths are the
first available of the following values:
1. CMAKE_PKG_CONFIG_PC_PATH
2. The PKG_CONFIG_PATH environment variable
3. Empty list
DISABLE_UNINSTALLED <bool>
Overrides the search behavior for "uninstalled" package files.
These are package files with an "-uninstalled" suffix which
describe packages integrated directly from a build tree.
Normally such package files have higher priority than
"installed" packages. When DISABLE_UNINSTALLED is true,
searching for "uninstalled" packages is disabled.
When this option is not provided, the default search behavior is
determined by the first available of the following values:
1. CMAKE_PKG_CONFIG_DISABLE_UNINSTALLED
2. If the PKG_CONFIG_DISABLE_UNINSTALLED environment variable is
defined the search is disabled, otherwise it is enabled.
PC_SYSROOT_DIR <path>
Overrides the root path which will be prepended to paths
specified by -I compile flags and -L library search locations;
also used to derive the pc_sysrootdir package variable.
When this option is not provided, the default root path is
provided by the first available of the following values:
1. CMAKE_PKG_CONFIG_SYSROOT_DIR
2. The PKG_CONFIG_SYSROOT_DIR environment variable
3. If no root path is available, nothing will be prepended to
include or library directory paths and pc_sysrootdir will be
set to /
TOP_BUILD_DIR <path>
Overrides the top build directory path used to derived the
pc_top_builddir package variable.
When this option is not provided, the default top build
directory path is the first available of the following values:
1. CMAKE_PKG_CONFIG_TOP_BUILD_DIR
2. The PKG_CONFIG_TOP_BUILD_DIR environment variable
3. If no top build directory path is available, the
pc_top_builddir package variable is not set
Signatures
cmake_pkg_config(EXTRACT <package> [<version>] [...])
Extract the contents of the package into variables.
cmake_pkg_config(EXTRACT <package> [<version>]
[REQUIRED] [EXACT] [QUIET]
[STRICTNESS <mode>]
[ENV_MODE <mode>]
[PC_LIBDIR <path>...]
[PC_PATH <path>...]
[DISABLE_UNINSTALLED <bool>]
[PC_SYSROOT_DIR <path>]
[TOP_BUILD_DIR <path>]
[SYSTEM_INCLUDE_DIRS <path>...]
[SYSTEM_LIBRARY_DIRS <path>...]
[ALLOW_SYSTEM_INCLUDES <bool>]
[ALLOW_SYSTEM_LIBS <bool>])
The following variables will be populated from the contents of package
file:
+---------------------------------+--------+-------------------------+
|Variable | Type | Definition |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_NAME | String | Value of the Name |
| | | keyword |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_DESCRIPTION | String | Value of the |
| | | Description keyword |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_VERSION | String | Value of the Version |
| | | keyword |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_PROVIDES | List | Value of the Provides |
| | | keyword |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_REQUIRES | List | Value of the Requires |
| | | keyword |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_CONFLICTS | List | Value of the Conflicts |
| | | keyword |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_CFLAGS | String | Value of the CFlags / |
| | | Cflags keyword |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_INCLUDES | List | All -I prefixed flags |
| | | from |
| | | CMAKE_PKG_CONFIG_CFLAGS |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_COMPILE_OPTIONS | List | All flags not prefixed |
| | | with -I from |
| | | CMAKE_PKG_CONFIG_CFLAGS |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_LIBS | String | Value of the Libs |
| | | keyword |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_LIBDIRS | List | All -L prefixed flags |
| | | from |
| | | CMAKE_PKG_CONFIG_LIBS |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_LIBNAMES | List | All -l prefixed flags |
| | | from |
| | | CMAKE_PKG_CONFIG_LIBS |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_LINK_OPTIONS | List | All flags not prefixed |
| | | with -L or -l from |
| | | CMAKE_PKG_CONFIG_LIBS |
+---------------------------------+--------+-------------------------+
|CMAKE_PKG_CONFIG_*_PRIVATE | * | CFLAGS / LIBS / |
| | | REQUIRES and derived, |
| | | but in their .private |
| | | suffix forms |
+---------------------------------+--------+-------------------------+
SYSTEM_INCLUDE_DIRS
Overrides the "system" directories for the purpose of flag
mangling include directories in CMAKE_PKG_CONFIG_CFLAGS and
derived variables.
When this option is not provided, the default directories are
provided by the first available of the following values:
1. CMAKE_PKG_CONFIG_SYS_INCLUDE_DIRS
2. The PKG_CONFIG_SYSTEM_INCLUDE_PATH environment variable
3. The output of pkgconf --variable pc_system_includedirs
pkg-config
4. A platform-dependent default value
Additionally, when the ENV_MODE is PKGCONF the
CMAKE_PKG_CONFIG_PKGCONF_INCLUDES variable will be concatenated
to the list if available. If it is not available, the following
environment variables will be queried and concatenated:
o CPATH
o C_INCLUDE_PATH
o CPLUS_INCLUDE_PATH
o OBJC_INCLUDE_PATH
o INCLUDE (Windows Only)
SYSTEM_LIBRARY_DIRS
Overrides the "system" directories for the purpose of flag
mangling library directories in CMAKE_PKG_CONFIG_LIBS and
derived variables.
When this option is not provided, the default directories are
provided by the first available of the following values:
1. CMAKE_PKG_CONFIG_SYS_LIB_DIRS
2. The PKG_CONFIG_SYSTEM_LIBRARY_PATH environment variable
3. The output of pkgconf --variable pc_system_libdirs pkg-config
4. A platform-dependent default value
Additionally, when the ENV_MODE is PKGCONF the
CMAKE_PKG_CONFIG_PKGCONF_LIB_DIRS variable will be concatenated
to the list if available. If it is not available, the
LIBRARY_PATH environment variable will be queried and
concatenated.
ALLOW_SYSTEM_INCLUDES
Preserves "system" directories during flag mangling of include
directories in CMAKE_PKG_CONFIG_CFLAGS and derived variables.
When this option is not provided, the default value is
determined by the first available of the following values:
1. CMAKE_PKG_CONFIG_ALLOW_SYS_INCLUDES
2. If the PKG_CONFIG_ALLOW_SYSTEM_CFLAGS environment variable is
defined the flags are preserved, otherwise they are filtered
during flag mangling.
ALLOW_SYSTEM_LIBS
Preserves "system" directories during flag mangling of library
directories in CMAKE_PKG_CONFIG_LIBS and derived variables.
When this option is not provided, the default value is
determined by the first available of the following values:
1. CMAKE_PKG_CONFIG_ALLOW_SYS_LIBS
2. If the PKG_CONFIG_ALLOW_SYSTEM_LIBS environment variable is
defined the flags are preserved, otherwise they are filtered
during flag mangling.
cmake_policy
Manage CMake Policy settings. See the cmake-policies(7) <#
manual:cmake-policies(7)> manual for defined policies.
As CMake evolves it is sometimes necessary to change existing behavior
in order to fix bugs or improve implementations of existing features.
The CMake Policy mechanism is designed to help keep existing projects
building as new versions of CMake introduce changes in behavior. Each
new policy (behavioral change) is given an identifier of the form
CMP<NNNN> where <NNNN> is an integer index. Documentation associated
with each policy describes the OLD and NEW behavior and the reason the
policy was introduced. Projects may set each policy to select the
desired behavior. When CMake needs to know which behavior to use it
checks for a setting specified by the project. If no setting is
available the OLD behavior is assumed and a warning is produced
requesting that the policy be set.
Setting Policies by CMake Version
The cmake_policy command is used to set policies to OLD or NEW
behavior. While setting policies individually is supported, we
encourage projects to set policies based on CMake versions:
cmake_policy(VERSION <min>[...<max>])
Added in version 3.12: The optional <max> version.
<min> and the optional <max> are each CMake versions of the form
major.minor[.patch[.tweak]], and the ... is literal. The <min> version
must be at least 2.4 and at most the running version of CMake. The
<max> version, if specified, must be at least the <min> version but may
exceed the running version of CMake. If the running version of CMake
is older than 3.12, the extra ... dots will be seen as version
component separators, resulting in the ...<max> part being ignored and
preserving the pre-3.12 behavior of basing policies on <min>.
This specifies that the current CMake code is written for the given
range of CMake versions. All policies known to the running version of
CMake and introduced in the <min> (or <max>, if specified) version or
earlier will be set to use NEW behavior. All policies introduced in
later versions will be unset (unless the CMAKE_POLICY_DEFAULT_CMP<NNNN>
<#variable:CMAKE_POLICY_DEFAULT_CMP<NNNN>> variable sets a default).
This effectively requests behavior preferred as of a given CMake
version and tells newer CMake versions to warn about their new
policies.
Note that the cmake_minimum_required(VERSION) <#
command:cmake_minimum_required> command implicitly calls
cmake_policy(VERSION) too.
Changed in version 3.31: Compatibility with versions of CMake older
than 3.10 is deprecated. Calls to cmake_minimum_required(VERSION) <#
command:cmake_minimum_required> or cmake_policy(VERSION) that do not
specify at least 3.10 as their policy version (optionally via ...<max>)
will produce a deprecation warning in CMake 3.31 and above.
Changed in version 3.27: Compatibility with versions of CMake older
than 3.5 is deprecated. Calls to cmake_minimum_required(VERSION) <#
command:cmake_minimum_required> or cmake_policy(VERSION) that do not
specify at least 3.5 as their policy version (optionally via ...<max>)
will produce a deprecation warning in CMake 3.27 and above.
Changed in version 3.19: Compatibility with versions of CMake older
than 2.8.12 is deprecated. Calls to cmake_minimum_required(VERSION) <#
command:cmake_minimum_required> or cmake_policy(VERSION) that do not
specify at least 2.8.12 as their policy version (optionally via
...<max>) will produce a deprecation warning in CMake 3.19 and above.
Setting Policies Explicitly
cmake_policy(SET CMP<NNNN> NEW|OLD)
Tell CMake to use the OLD or NEW behavior for a given policy. Projects
depending on the old behavior of a given policy may silence a policy
warning by setting the policy state to OLD. Alternatively one may fix
the project to work with the new behavior and set the policy state to
NEW.
Note:
The OLD behavior of a policy is deprecated by definition <#
manual:cmake-policies(7)> and may be removed in a future version of
CMake.
Checking Policy Settings
cmake_policy(GET CMP<NNNN> <variable>)
Check whether a given policy is set to OLD or NEW behavior. The output
<variable> value will be OLD or NEW if the policy is set, and empty
otherwise.
CMake Policy Stack
CMake keeps policy settings on a stack, so changes made by the
cmake_policy command affect only the top of the stack. A new entry on
the policy stack is managed automatically for each subdirectory to
protect its parents and siblings. CMake also manages a new entry for
scripts loaded by include() <#command:include> and find_package() <#
command:find_package> commands except when invoked with the
NO_POLICY_SCOPE option (see also policy CMP0011 <#policy:CMP0011>).
The cmake_policy command provides an interface to manage custom entries
on the policy stack:
cmake_policy(PUSH)
Create a new entry on the policy stack.
cmake_policy(POP)
Remove the last policy stack entry created with
cmake_policy(PUSH).
Each PUSH must have a matching POP to erase any changes. This is
useful to make temporary changes to policy settings. Calls to the
cmake_minimum_required(VERSION) <#command:cmake_minimum_required>,
cmake_policy(VERSION), or cmake_policy(SET) commands influence only the
current top of the policy stack.
Added in version 3.25: The block(SCOPE_FOR POLICIES) <#command:block>
command offers a more flexible and more secure way to manage the policy
stack. The pop action is done automatically when leaving the block
scope, so there is no need to precede each return() <#command:return>
with a call to cmake_policy(POP).
# stack management with cmake_policy()
function(my_func)
cmake_policy(PUSH)
cmake_policy(SET ...)
if (<cond1>)
...
cmake_policy(POP)
return()
elseif(<cond2>)
...
cmake_policy(POP)
return()
endif()
...
cmake_policy(POP)
endfunction()
# stack management with block()/endblock()
function(my_func)
block(SCOPE_FOR POLICIES)
cmake_policy(SET ...)
if (<cond1>)
...
return()
elseif(<cond2>)
...
return()
endif()
...
endblock()
endfunction()
Commands created by the function() <#command:function> and macro() <#
command:macro> commands record policy settings when they are created
and use the pre-record policies when they are invoked. If the function
or macro implementation sets policies, the changes automatically
propagate up through callers until they reach the closest nested policy
stack entry.
See Also
o cmake_minimum_required() <#command:cmake_minimum_required>
configure_file
Copy a file to another location and modify its contents.
configure_file(<input> <output>
[NO_SOURCE_PERMISSIONS | USE_SOURCE_PERMISSIONS |
FILE_PERMISSIONS <permissions>...]
[COPYONLY] [ESCAPE_QUOTES] [@ONLY]
[NEWLINE_STYLE [UNIX|DOS|WIN32|LF|CRLF] ])
Copies an <input> file to an <output> file while performing
transformations of the input file content.
If the input file is modified the build system will re-run CMake to
re-configure the file and generate the build system again. The
generated file is modified and its timestamp updated on subsequent
cmake runs only if its content is changed.
Options
The options are:
<input>
Path to the input file. A relative path is treated with respect
to the value of CMAKE_CURRENT_SOURCE_DIR <#
variable:CMAKE_CURRENT_SOURCE_DIR>. The input path must be a
file, not a directory.
<output>
Path to the output file or directory. A relative path is
treated with respect to the value of CMAKE_CURRENT_BINARY_DIR <#
variable:CMAKE_CURRENT_BINARY_DIR>. If the path names an
existing directory the output file is placed in that directory
with the same file name as the input file. If the path contains
non-existent directories, they are created.
NO_SOURCE_PERMISSIONS
Added in version 3.19.
Do not transfer the permissions of the input file to the output
file. The copied file permissions default to the standard 644
value (-rw-r--r--).
USE_SOURCE_PERMISSIONS
Added in version 3.20.
Transfer the permissions of the input file to the output file.
This is already the default behavior if none of the three
permissions-related keywords are given (NO_SOURCE_PERMISSIONS,
USE_SOURCE_PERMISSIONS or FILE_PERMISSIONS). The
USE_SOURCE_PERMISSIONS keyword mostly serves as a way of making
the intended behavior clearer at the call site.
FILE_PERMISSIONS <permissions>...
Added in version 3.20.
Ignore the input file's permissions and use the specified
<permissions> for the output file instead.
COPYONLY
Copy the file without replacing any variable references or other
content. This option may not be used with NEWLINE_STYLE.
ESCAPE_QUOTES
Escape any substituted quotes with backslashes (C-style).
@ONLY Restrict variable replacement to references of the form @VAR@.
This is useful for configuring scripts that use ${VAR} syntax.
NEWLINE_STYLE <style>
Specify the newline style for the output file. Specify UNIX or
LF for \n newlines, or specify DOS, WIN32, or CRLF for \r\n
newlines. This option may not be used with COPYONLY.
Transformations
Variables <#cmake-language-variables> referenced in the input file
content as @VAR@, ${VAR}, $CACHE{VAR}, and environment variables <#
cmake-language-environment-variables> referenced as $ENV{VAR}, will
each be replaced with the current value of the variable, or the empty
string if the variable is not defined. Furthermore, input lines of the
form
#cmakedefine VAR ...
will be replaced with either
#define VAR ...
or
/* #undef VAR */
depending on whether VAR is set in CMake to any value not considered a
false constant by the if() <#command:if> command. The "..." content on
the line after the variable name, if any, is processed as above.
Unlike lines of the form #cmakedefine VAR ..., in lines of the form
#cmakedefine01 VAR, VAR itself will expand to VAR 0 or VAR 1 rather
than being assigned the value .... Therefore, input lines of the form
#cmakedefine01 VAR
will be replaced with either
#define VAR 0
or
#define VAR 1
Input lines of the form #cmakedefine01 VAR ... will expand as
#cmakedefine01 VAR ... 0 or #cmakedefine01 VAR ... 1, which may lead to
undefined behavior.
Added in version 3.10: The result lines (with the exception of the
#undef comments) can be indented using spaces and/or tabs between the #
character and the cmakedefine or cmakedefine01 words. This whitespace
indentation will be preserved in the output lines:
# cmakedefine VAR
# cmakedefine01 VAR
will be replaced, if VAR is defined, with
# define VAR
# define VAR 1
Example
Consider a source tree containing a foo.h.in file:
#cmakedefine FOO_ENABLE
#cmakedefine FOO_STRING "@FOO_STRING@"
An adjacent CMakeLists.txt may use configure_file to configure the
header:
option(FOO_ENABLE "Enable Foo" ON)
if(FOO_ENABLE)
set(FOO_STRING "foo")
endif()
configure_file(foo.h.in foo.h @ONLY)
This creates a foo.h in the build directory corresponding to this
source directory. If the FOO_ENABLE option is on, the configured file
will contain:
#define FOO_ENABLE
#define FOO_STRING "foo"
Otherwise it will contain:
/* #undef FOO_ENABLE */
/* #undef FOO_STRING */
One may then use the target_include_directories() <#
command:target_include_directories> command to specify the output
directory as an include directory:
target_include_directories(<target> [SYSTEM] <INTERFACE|PUBLIC|PRIVATE> "${CMAKE_CURRENT_BINARY_DIR}")
so that sources may include the header as #include <foo.h>.
See Also
o file(GENERATE) <#generate>
continue
Added in version 3.2.
Continue to the top of enclosing foreach or while loop.
continue()
The continue() command allows a cmake script to abort the rest of the
current iteration of a foreach() <#command:foreach> or while() <#
command:while> loop, and start at the top of the next iteration.
See also the break() <#command:break> command.
else
Starts the else portion of an if block.
else([<condition>])
See the if() <#command:if> command.
elseif
Starts an elseif portion of an if block.
elseif(<condition>)
See the if() <#command:if> command, especially for the syntax and logic
of the <condition>.
endblock
Added in version 3.25.
Ends a list of commands in a block() <#command:block> and removes the
scopes created by the block() <#command:block> command.
endblock()
endforeach
Ends a list of commands in a foreach block.
endforeach([<loop_var>])
See the foreach() <#command:foreach> command.
The optional <loop_var> argument is supported for backward
compatibility only. If used it must be a verbatim repeat of the
<loop_var> argument of the opening foreach clause.
endfunction
Ends a list of commands in a function block.
endfunction([<name>])
See the function() <#command:function> command.
The optional <name> argument is supported for backward compatibility
only. If used it must be a verbatim repeat of the <name> argument of
the opening function command.
endif
Ends a list of commands in an if block.
endif([<condition>])
See the if() <#command:if> command.
The optional <condition> argument is supported for backward
compatibility only. If used it must be a verbatim repeat of the
argument of the opening if clause.
endmacro
Ends a list of commands in a macro block.
endmacro([<name>])
See the macro() <#command:macro> command.
The optional <name> argument is supported for backward compatibility
only. If used it must be a verbatim repeat of the <name> argument of
the opening macro command.
endwhile
Ends a list of commands in a while block.
endwhile([<condition>])
See the while() <#command:while> command.
The optional <condition> argument is supported for backward
compatibility only. If used it must be a verbatim repeat of the
argument of the opening while clause.
execute_process
Execute one or more child processes.
execute_process(COMMAND <cmd1> [<arguments>]
[COMMAND <cmd2> [<arguments>]]...
[WORKING_DIRECTORY <directory>]
[TIMEOUT <seconds>]
[RESULT_VARIABLE <variable>]
[RESULTS_VARIABLE <variable>]
[OUTPUT_VARIABLE <variable>]
[ERROR_VARIABLE <variable>]
[INPUT_FILE <file>]
[OUTPUT_FILE <file>]
[ERROR_FILE <file>]
[OUTPUT_QUIET]
[ERROR_QUIET]
[COMMAND_ECHO <where>]
[OUTPUT_STRIP_TRAILING_WHITESPACE]
[ERROR_STRIP_TRAILING_WHITESPACE]
[ENCODING <name>]
[ECHO_OUTPUT_VARIABLE]
[ECHO_ERROR_VARIABLE]
[COMMAND_ERROR_IS_FATAL <ANY|LAST>])
Runs the given sequence of one or more commands.
Commands are executed concurrently as a pipeline, with the standard
output of each process piped to the standard input of the next. A
single standard error pipe is used for all processes.
execute_process runs commands while CMake is configuring the project,
prior to build system generation. Use the add_custom_target() <#
command:add_custom_target> and add_custom_command() <#
command:add_custom_command> commands to create custom commands that run
at build time.
Options:
COMMAND
A child process command line.
CMake executes the child process using operating system APIs
directly:
o On POSIX platforms, the command line is passed to the child
process in an argv[] style array.
o On Windows platforms, the command line is encoded as a string
such that child processes using CommandLineToArgvW will decode
the original arguments.
No intermediate shell is used, so shell operators such as > are
treated as normal arguments. (Use the INPUT_*, OUTPUT_*, and
ERROR_* options to redirect stdin, stdout, and stderr.)
For sequential execution of multiple commands use multiple
execute_process calls each with a single COMMAND argument.
WORKING_DIRECTORY
The named directory will be set as the current working directory
of the child processes.
TIMEOUT
After the specified number of seconds (fractions allowed), all
unfinished child processes will be terminated, and the
RESULT_VARIABLE will be set to a string mentioning the
"timeout".
RESULT_VARIABLE
The variable will be set to contain the result of last child
process. This will be an integer return code from the last
child or a string describing an error condition.
RESULTS_VARIABLE <variable>
Added in version 3.10.
The variable will be set to contain the result of all processes
as a semicolon-separated list <#cmake-language-lists>, in order
of the given COMMAND arguments. Each entry will be an integer
return code from the corresponding child or a string describing
an error condition.
INPUT_FILE <file>
<file> is attached to the standard input pipe of the first
COMMAND process.
OUTPUT_FILE <file>
<file> is attached to the standard output pipe of the last
COMMAND process.
ERROR_FILE <file>
<file> is attached to the standard error pipe of all COMMAND
processes.
Added in version 3.3: If the same <file> is named for both OUTPUT_FILE
and ERROR_FILE then it will be used for both standard output and
standard error pipes.
OUTPUT_QUIET, ERROR_QUIET
The standard output on OUTPUT_VARIABLE or standard error on
ERROR_VARIABLE are not connected (no variable content). The
*_FILE and ECHO_*_VARIABLE options are not affected.
OUTPUT_VARIABLE, ERROR_VARIABLE
The variable named will be set with the contents of the standard
output and standard error pipes, respectively. If the same
variable is named for both pipes their output will be merged in
the order produced.
ECHO_OUTPUT_VARIABLE, ECHO_ERROR_VARIABLE
Added in version 3.18.
The standard output or standard error will not be exclusively
redirected to the specified variables.
The output will be duplicated into the specified variables and
also onto standard output or standard error analogous to the tee
Unix command.
Note:
If more than one OUTPUT_* or ERROR_* option is given for the same
pipe the precedence is not specified. If no OUTPUT_* or ERROR_*
options are given the output will be shared with the corresponding
pipes of the CMake process itself.
COMMAND_ECHO <where>
Added in version 3.15.
The command being run will be echo'ed to <where> with <where>
being set to one of STDERR, STDOUT or NONE. See the
CMAKE_EXECUTE_PROCESS_COMMAND_ECHO <#
variable:CMAKE_EXECUTE_PROCESS_COMMAND_ECHO> variable for a way
to control the default behavior when this option is not present.
ENCODING <name>
Added in version 3.8.
On Windows, the encoding that is used to decode output from the
process. Ignored on other platforms. Valid encoding names are:
NONE Perform no decoding. This assumes that the process
output is encoded in the same way as CMake's internal
encoding (UTF-8).
This was the default in CMake 3.14 and older.
AUTO Use the current active console's codepage or if that
isn't available then use ANSI.
This was the default in CMake 3.15 through 3.30.
ANSI Use the ANSI codepage.
OEM Use the original equipment manufacturer (OEM) code page.
UTF-8 Added in version 3.11.
Use the UTF-8 codepage.
This is the default since CMake 3.31. See policy CMP0176
<#policy:CMP0176>.
UTF8 Use the UTF-8 codepage. Use of this name is discouraged
in favor of UTF-8 to match the UTF-8 RFC <https://
datatracker.ietf.org/doc/html/rfc3629> naming convention.
COMMAND_ERROR_IS_FATAL <ANY|LAST>
Added in version 3.19.
The option following COMMAND_ERROR_IS_FATAL determines the
behavior when an error is encountered:
ANY If any of the commands in the list of commands fail, the
execute_process() command halts with an error.
LAST If the last command in the list of commands fails, the
execute_process() command halts with an error. Commands
earlier in the list will not cause a fatal error.
file
File manipulation command.
This command is dedicated to file and path manipulation requiring
access to the filesystem.
For other path manipulation, handling only syntactic aspects, have a
look at cmake_path() <#command:cmake_path> command.
Note:
The sub-commands RELATIVE_PATH, TO_CMAKE_PATH and TO_NATIVE_PATH has
been superseded, respectively, by sub-commands RELATIVE_PATH <#
cmake-path-relative-path>, CONVERT ... TO_CMAKE_PATH_LIST <#cmake-
path-to-cmake-path-list> and CONVERT ... TO_NATIVE_PATH_LIST <#
cmake-path-to-native-path-list> of cmake_path() <#
command:cmake_path> command.
Synopsis
Reading
file(READ <filename> <out-var> [...])
file(STRINGS <filename> <out-var> [...])
file(<HASH> <filename> <out-var>)
file(TIMESTAMP <filename> <out-var> [...])
Writing
file({WRITE | APPEND} <filename> <content>...)
file({TOUCH | TOUCH_NOCREATE} <file>...)
file(GENERATE OUTPUT <output-file> [...])
file(CONFIGURE OUTPUT <output-file> CONTENT <content> [...])
Filesystem
file({GLOB | GLOB_RECURSE} <out-var> [...] <globbing-expr>...)
file(MAKE_DIRECTORY <directories>...)
file({REMOVE | REMOVE_RECURSE } <files>...)
file(RENAME <oldname> <newname> [...])
file(COPY_FILE <oldname> <newname> [...])
file({COPY | INSTALL} <file>... DESTINATION <dir> [...])
file(SIZE <filename> <out-var>)
file(READ_SYMLINK <linkname> <out-var>)
file(CREATE_LINK <original> <linkname> [...])
file(CHMOD <files>... <directories>... PERMISSIONS <permissions>... [...])
file(CHMOD_RECURSE <files>... <directories>... PERMISSIONS <permissions>... [...])
Path Conversion
file(REAL_PATH <path> <out-var> [BASE_DIRECTORY <dir>] [EXPAND_TILDE])
file(RELATIVE_PATH <out-var> <directory> <file>)
file({TO_CMAKE_PATH | TO_NATIVE_PATH} <path> <out-var>)
Transfer
file(DOWNLOAD <url> [<file>] [...])
file(UPLOAD <file> <url> [...])
Locking
file(LOCK <path> [...])
Archiving
file(ARCHIVE_CREATE OUTPUT <archive> PATHS <paths>... [...])
file(ARCHIVE_EXTRACT INPUT <archive> [...])
Handling Runtime Binaries
file(GET_RUNTIME_DEPENDENCIES [...])
Reading
file(READ <filename> <variable> [OFFSET <offset>] [LIMIT <max-in>]
[HEX]) Read content from a file called <filename> and store it in a
<variable>. Optionally start from the given <offset> and read
at most <max-in> bytes. The HEX option causes data to be
converted to a hexadecimal representation (useful for binary
data). If the HEX option is specified, letters in the output (a
through f) are in lowercase.
file(STRINGS <filename> <variable> <options>...)
Parse a list of ASCII strings from <filename> and store it in
<variable>. Binary data in the file are ignored. Carriage
return (\r, CR) characters are ignored. The options are:
LENGTH_MAXIMUM <max-len>
Consider only strings of at most a given length.
LENGTH_MINIMUM <min-len>
Consider only strings of at least a given length.
LIMIT_COUNT <max-num>
Limit the number of distinct strings to be extracted.
LIMIT_INPUT <max-in>
Limit the number of input bytes to read from the file.
LIMIT_OUTPUT <max-out>
Limit the number of total bytes to store in the
<variable>.
NEWLINE_CONSUME
Treat newline characters (\n, LF) as part of string
content instead of terminating at them.
NO_HEX_CONVERSION
Intel Hex and Motorola S-record files are
automatically converted to binary while reading unless
this option is given.
REGEX <regex>
Consider only strings that match the given regular
expression, as described under string(REGEX) <#regex-
specification>.
Changed in version 3.29: Capture groups from the last
match in the file are stored in CMAKE_MATCH_<n> <#
variable:CMAKE_MATCH_<n>>, similar to string(REGEX
MATCHALL) <#regex-matchall>. See policy CMP0159 <#
policy:CMP0159>.
ENCODING <encoding-type>
Added in version 3.1.
Consider strings of a given encoding. Currently
supported encodings are: UTF-8, UTF-16LE, UTF-16BE,
UTF-32LE, UTF-32BE. If the ENCODING option is not
provided and the file has a Byte Order Mark, the
ENCODING option will be defaulted to respect the Byte
Order Mark.
Added in version 3.2: Added the UTF-16LE, UTF-16BE, UTF-32LE,
UTF-32BE encodings.
For example, the code
file(STRINGS myfile.txt myfile)
stores a list in the variable myfile in which each item is a
line from the input file.
file(<HASH> <filename> <variable>)
Compute a cryptographic hash of the content of <filename> and
store it in a <variable>. The supported <HASH> algorithm names
are those listed by the string(<HASH>) <#hash> command.
file(TIMESTAMP <filename> <variable> [<format>] [UTC])
Compute a string representation of the modification time of
<filename> and store it in <variable>. Should the command be
unable to obtain a timestamp variable will be set to the empty
string ("").
See the string(TIMESTAMP) <#timestamp> command for documentation
of the <format> and UTC options.
Writing
file(WRITE <filename> <content>...)
file(APPEND <filename> <content>...)
Write <content> into a file called <filename>. If the file does
not exist, it will be created. If the file already exists,
WRITE mode will overwrite it and APPEND mode will append to the
end. Any directories in the path specified by <filename> that
do not exist will be created.
If the file is a build input, use the configure_file() <#
command:configure_file> command to update the file only when its
content changes.
file(TOUCH <files>...)
file(TOUCH_NOCREATE <files>...)
Added in version 3.12.
Create a file with no content if it does not yet exist. If the
file already exists, its access and/or modification will be
updated to the time when the function call is executed.
Use TOUCH_NOCREATE to touch a file if it exists but not create
it. If a file does not exist it will be silently ignored.
With TOUCH and TOUCH_NOCREATE, the contents of an existing file
will not be modified.
Changed in version 3.30: <files> can be an empty list. CMake
3.29 and earlier required at least one file to be given.
file(GENERATE [...])
Generate an output file for each build configuration supported
by the current CMake Generator <#manual:cmake-generators(7)>.
Evaluate generator expressions <#manual:cmake-generator-
expressions(7)> from the input content to produce the output
content.
file(GENERATE OUTPUT <output-file>
<INPUT <input-file>|CONTENT <content>>
[CONDITION <expression>] [TARGET <target>]
[NO_SOURCE_PERMISSIONS | USE_SOURCE_PERMISSIONS |
FILE_PERMISSIONS <permissions>...]
[NEWLINE_STYLE [UNIX|DOS|WIN32|LF|CRLF] ])
The options are:
CONDITION <condition>
Generate the output file for a particular
configuration only if the condition is true. The
condition must be either 0 or 1 after evaluating
generator expressions.
CONTENT <content>
Use the content given explicitly as input.
INPUT <input-file>
Use the content from a given file as input.
Changed in version 3.10: A relative path is treated
with respect to the value of CMAKE_CURRENT_SOURCE_DIR
<#variable:CMAKE_CURRENT_SOURCE_DIR>. See policy
CMP0070 <#policy:CMP0070>.
OUTPUT <output-file>
Specify the output file name to generate. Use
generator expressions such as $<CONFIG> <#
genex:CONFIG> to specify a configuration-specific
output file name. Multiple configurations may
generate the same output file only if the generated
content is identical. Otherwise, the <output-file>
must evaluate to an unique name for each
configuration.
Changed in version 3.10: A relative path (after
evaluating generator expressions) is treated with
respect to the value of CMAKE_CURRENT_BINARY_DIR <#
variable:CMAKE_CURRENT_BINARY_DIR>. See policy
CMP0070 <#policy:CMP0070>.
TARGET <target>
Added in version 3.19.
Specify which target to use when evaluating generator
expressions that require a target for evaluation (e.g.
$<COMPILE_FEATURES:...> <#genex:COMPILE_FEATURES>,
$<TARGET_PROPERTY:prop> <#genex:TARGET_PROPERTY>).
NO_SOURCE_PERMISSIONS
Added in version 3.20.
The generated file permissions default to the standard
644 value (-rw-r--r--).
USE_SOURCE_PERMISSIONS
Added in version 3.20.
Transfer the file permissions of the INPUT file to the
generated file. This is already the default behavior
if none of the three permissions-related keywords are
given (NO_SOURCE_PERMISSIONS, USE_SOURCE_PERMISSIONS
or FILE_PERMISSIONS). The USE_SOURCE_PERMISSIONS
keyword mostly serves as a way of making the intended
behavior clearer at the call site. It is an error to
specify this option without INPUT.
FILE_PERMISSIONS <permissions>...
Added in version 3.20.
Use the specified permissions for the generated file.
NEWLINE_STYLE <style>
Added in version 3.20.
Specify the newline style for the generated file.
Specify UNIX or LF for \n newlines, or specify DOS,
WIN32, or CRLF for \r\n newlines.
Exactly one CONTENT or INPUT option must be given. A specific
OUTPUT file may be named by at most one invocation of
file(GENERATE). Generated files are modified and their
timestamp updated on subsequent cmake runs only if their content
is changed.
Note also that file(GENERATE) does not create the output file
until the generation phase. The output file will not yet have
been written when the file(GENERATE) command returns, it is
written only after processing all of a project's CMakeLists.txt
files.
file(CONFIGURE OUTPUT <output-file> CONTENT <content> [ESCAPE_QUOTES]
[@ONLY] [NEWLINE_STYLE [UNIX|DOS|WIN32|LF|CRLF] ])
Added in version 3.18.
Generate an output file using the input given by CONTENT and
substitute variable values referenced as @VAR@ or ${VAR}
contained therein. The substitution rules behave the same as the
configure_file() <#command:configure_file> command. In order to
match configure_file() <#command:configure_file>'s behavior,
generator expressions are not supported for both OUTPUT and
CONTENT, and the output file is only modified and its timestamp
updated if the content is changed or the file previously didn't
exist.
The arguments are:
OUTPUT <output-file>
Specify the output file name to generate. A relative
path is treated with respect to the value of
CMAKE_CURRENT_BINARY_DIR <#
variable:CMAKE_CURRENT_BINARY_DIR>. <output-file>
does not support generator expressions.
CONTENT <content>
Use the content given explicitly as input. <content>
does not support generator expressions.
ESCAPE_QUOTES
Escape any substituted quotes with backslashes
(C-style).
@ONLY Restrict variable replacement to references of the
form @VAR@. This is useful for configuring scripts
that use ${VAR} syntax.
NEWLINE_STYLE <style>
Specify the newline style for the output file.
Specify UNIX or LF for \n newlines, or specify DOS,
WIN32, or CRLF for \r\n newlines.
Filesystem
file(GLOB <variable> [LIST_DIRECTORIES true|false] [RELATIVE <path>]
[CONFIGURE_DEPENDS] <globbing-expressions>...)
file(GLOB_RECURSE <variable> [FOLLOW_SYMLINKS]
[LIST_DIRECTORIES true|false] [RELATIVE <path>] [CONFIGURE_DEPENDS]
<globbing-expressions>...)
Generate a list of files that match the <globbing-expressions>
and store it into the <variable>. Globbing expressions are
similar to regular expressions, but much simpler. If RELATIVE
flag is specified, the results will be returned as relative
paths to the given path.
Changed in version 3.6: The results will be ordered
lexicographically.
On Windows and macOS, globbing is case-insensitive even if the
underlying filesystem is case-sensitive (both filenames and
globbing expressions are converted to lowercase before
matching). On other platforms, globbing is case-sensitive.
Added in version 3.3: By default GLOB lists directories.
Directories are omitted in the result if LIST_DIRECTORIES is set
to false.
Added in version 3.12: If the CONFIGURE_DEPENDS flag is
specified, CMake will add logic to the main build system check
target to rerun the flagged GLOB commands at build time. If any
of the outputs change, CMake will regenerate the build system.
Note:
We do not recommend using GLOB to collect a list of source
files from your source tree. If no CMakeLists.txt file
changes when a source is added or removed then the generated
build system cannot know when to ask CMake to regenerate.
The CONFIGURE_DEPENDS flag may not work reliably on all
generators, or if a new generator is added in the future that
cannot support it, projects using it will be stuck. Even if
CONFIGURE_DEPENDS works reliably, there is still a cost to
perform the check on every rebuild.
Examples of globbing expressions include:
+-----------+-------------------------+
|*.cxx | match all files with |
| | extension cxx |
+-----------+-------------------------+
|*.vt? | match all files with |
| | extension vta, ..., vtz |
+-----------+-------------------------+
|f[3-5].txt | match files f3.txt, |
| | f4.txt, f5.txt |
+-----------+-------------------------+
The GLOB_RECURSE mode will traverse all the subdirectories of
the matched directory and match the files. Subdirectories that
are symlinks are only traversed if FOLLOW_SYMLINKS is given or
policy CMP0009 <#policy:CMP0009> is not set to NEW.
Added in version 3.3: By default GLOB_RECURSE omits directories
from result list. Setting LIST_DIRECTORIES to true adds
directories to result list. If FOLLOW_SYMLINKS is given or
policy CMP0009 <#policy:CMP0009> is not set to NEW then
LIST_DIRECTORIES treats symlinks as directories.
Examples of recursive globbing include:
+----------+---------------------------+
|/dir/*.py | match all python files in |
| | /dir and subdirectories |
+----------+---------------------------+
file(MAKE_DIRECTORY <directories>... [RESULT <result>])
Create the given directories and their parents as needed.
The options are:
RESULT <result>
Added in version 3.31.
Set <result> variable to 0 on success or an error
message otherwise. If RESULT is not specified and the
operation fails, an error is emitted.
Changed in version 3.30: <directories> can be an empty list.
CMake 3.29 and earlier required at least one directory to be
given.
file(REMOVE <files>...)
file(REMOVE_RECURSE <files>...)
Remove the given files. The REMOVE_RECURSE mode will remove the
given files and directories, including non-empty directories. No
error is emitted if a given file does not exist. Relative input
paths are evaluated with respect to the current source
directory.
Changed in version 3.15: Empty input paths are ignored with a
warning. Previous versions of CMake interpreted empty strings
as a relative path with respect to the current directory and
removed its contents.
file(RENAME <oldname> <newname> [RESULT <result>] [NO_REPLACE])
Move a file or directory within a filesystem from <oldname> to
<newname>, replacing the destination atomically.
The options are:
RESULT <result>
Added in version 3.21.
Set <result> variable to 0 on success or an error
message otherwise. If RESULT is not specified and the
operation fails, an error is emitted.
NO_REPLACE
Added in version 3.21.
If the <newname> path already exists, do not replace
it. If RESULT <result> is used, the result variable
will be set to NO_REPLACE. Otherwise, an error is
emitted.
file(COPY_FILE <oldname> <newname> [RESULT <result>]
[ONLY_IF_DIFFERENT] [INPUT_MAY_BE_RECENT])
Added in version 3.21.
Copy a file from <oldname> to <newname>. Directories are not
supported. Symlinks are ignored and <oldfile>'s content is read
and written to <newname> as a new file.
The options are:
RESULT <result>
Set <result> variable to 0 on success or an error
message otherwise. If RESULT is not specified and the
operation fails, an error is emitted.
ONLY_IF_DIFFERENT
If the <newname> path already exists, do not replace
it if the file's contents are already the same as
<oldname> (this avoids updating <newname>'s
timestamp).
INPUT_MAY_BE_RECENT
Added in version 3.26.
Tell CMake that the input file may have been recently
created. This is meaningful only on Windows, where
files may be inaccessible for a short time after they
are created. With this option, if permission is
denied, CMake will retry reading the input a few
times.
This sub-command has some similarities to configure_file() <#
command:configure_file> with the COPYONLY option. An important
difference is that configure_file() <#command:configure_file>
creates a dependency on the source file, so CMake will be re-run
if it changes. The file(COPY_FILE) sub-command does not create
such a dependency.
See also the file(COPY) sub-command just below which provides
further file-copying capabilities.
file(COPY [...])
file(INSTALL [...])
The COPY signature copies files, directories, and symlinks to a
destination folder. Relative input paths are evaluated with
respect to the current source directory, and a relative
destination is evaluated with respect to the current build
directory. Copying preserves input file timestamps, and
optimizes out a file if it exists at the destination with the
same timestamp. Copying preserves input permissions unless
explicit permissions or NO_SOURCE_PERMISSIONS are given (default
is USE_SOURCE_PERMISSIONS).
file(<COPY|INSTALL> <files>... DESTINATION <dir>
[NO_SOURCE_PERMISSIONS | USE_SOURCE_PERMISSIONS]
[FILE_PERMISSIONS <permissions>...]
[DIRECTORY_PERMISSIONS <permissions>...]
[FOLLOW_SYMLINK_CHAIN]
[FILES_MATCHING]
[[PATTERN <pattern> | REGEX <regex>]
[EXCLUDE] [PERMISSIONS <permissions>...]] [...])
Note:
For a simple file copying operation, the file(COPY_FILE)
sub-command just above may be easier to use.
Added in version 3.15: If FOLLOW_SYMLINK_CHAIN is specified,
COPY will recursively resolve the symlinks at the paths given
until a real file is found, and install a corresponding symlink
in the destination for each symlink encountered. For each
symlink that is installed, the resolution is stripped of the
directory, leaving only the filename, meaning that the new
symlink points to a file in the same directory as the symlink.
This feature is useful on some Unix systems, where libraries are
installed as a chain of symlinks with version numbers, with less
specific versions pointing to more specific versions.
FOLLOW_SYMLINK_CHAIN will install all of these symlinks and the
library itself into the destination directory. For example, if
you have the following directory structure:
o /opt/foo/lib/libfoo.so.1.2.3
o /opt/foo/lib/libfoo.so.1.2 -> libfoo.so.1.2.3
o /opt/foo/lib/libfoo.so.1 -> libfoo.so.1.2
o /opt/foo/lib/libfoo.so -> libfoo.so.1
and you do:
file(COPY /opt/foo/lib/libfoo.so DESTINATION lib FOLLOW_SYMLINK_CHAIN)
This will install all of the symlinks and libfoo.so.1.2.3 itself
into lib.
See the install(DIRECTORY) <#directory> command for
documentation of permissions, FILES_MATCHING, PATTERN, REGEX,
and EXCLUDE options. Copying directories preserves the
structure of their content even if options are used to select a
subset of files.
The INSTALL signature differs slightly from COPY: it prints
status messages, and NO_SOURCE_PERMISSIONS is default.
Installation scripts generated by the install() <#
command:install> command use this signature (with some
undocumented options for internal use).
Changed in version 3.22: The environment variable
CMAKE_INSTALL_MODE <#envvar:CMAKE_INSTALL_MODE> can override the
default copying behavior of file(INSTALL).
file(SIZE <filename> <variable>)
Added in version 3.14.
Determine the file size of the <filename> and put the result in
<variable> variable. Requires that <filename> is a valid path
pointing to a file and is readable.
file(READ_SYMLINK <linkname> <variable>)
Added in version 3.14.
Query the symlink <linkname> and stores the path it points to in
the result <variable>. If <linkname> does not exist or is not a
symlink, CMake issues a fatal error.
Note that this command returns the raw symlink path and does not
resolve a relative path. The following is an example of how to
ensure that an absolute path is obtained:
set(linkname "/path/to/foo.sym")
file(READ_SYMLINK "${linkname}" result)
if(NOT IS_ABSOLUTE "${result}")
get_filename_component(dir "${linkname}" DIRECTORY)
set(result "${dir}/${result}")
endif()
file(CREATE_LINK <original> <linkname> [RESULT <result>]
[COPY_ON_ERROR] [SYMBOLIC])
Added in version 3.14.
Create a link <linkname> that points to <original>. It will be
a hard link by default, but providing the SYMBOLIC option
results in a symbolic link instead. Hard links require that
original exists and is a file, not a directory. If <linkname>
already exists, it will be overwritten.
The <result> variable, if specified, receives the status of the
operation. It is set to 0 upon success or an error message
otherwise. If RESULT is not specified and the operation fails,
a fatal error is emitted.
Specifying COPY_ON_ERROR enables copying the file as a fallback
if creating the link fails. It can be useful for handling
situations such as <original> and <linkname> being on different
drives or mount points, which would make them unable to support
a hard link.
file(CHMOD <files>... <directories>... [PERMISSIONS <permissions>...]
[FILE_PERMISSIONS <permissions>...]
[DIRECTORY_PERMISSIONS <permissions>...])
Added in version 3.19.
Set the permissions for the <files>... and <directories>...
specified. Valid permissions are OWNER_READ, OWNER_WRITE,
OWNER_EXECUTE, GROUP_READ, GROUP_WRITE, GROUP_EXECUTE,
WORLD_READ, WORLD_WRITE, WORLD_EXECUTE, SETUID, SETGID.
Valid combination of keywords are:
PERMISSIONS
All items are changed.
FILE_PERMISSIONS
Only files are changed.
DIRECTORY_PERMISSIONS
Only directories are changed.
PERMISSIONS and FILE_PERMISSIONS
FILE_PERMISSIONS overrides PERMISSIONS for files.
PERMISSIONS and DIRECTORY_PERMISSIONS
DIRECTORY_PERMISSIONS overrides PERMISSIONS for
directories.
FILE_PERMISSIONS and DIRECTORY_PERMISSIONS
Use FILE_PERMISSIONS for files and
DIRECTORY_PERMISSIONS for directories.
file(CHMOD_RECURSE <files>... <directories>...
[PERMISSIONS <permissions>...] [FILE_PERMISSIONS <permissions>...]
[DIRECTORY_PERMISSIONS <permissions>...])
Added in version 3.19.
Same as CHMOD, but change the permissions of files and
directories present in the <directories>... recursively.
Path Conversion
file(REAL_PATH <path> <out-var> [BASE_DIRECTORY <dir>] [EXPAND_TILDE])
Added in version 3.19.
Compute the absolute path to an existing file or directory with
symlinks resolved. The options are:
BASE_DIRECTORY <dir>
If the provided <path> is a relative path, it is
evaluated relative to the given base directory <dir>.
If no base directory is provided, the default base
directory will be CMAKE_CURRENT_SOURCE_DIR <#
variable:CMAKE_CURRENT_SOURCE_DIR>.
EXPAND_TILDE
Added in version 3.21.
If the <path> is ~ or starts with ~/, the ~ is
replaced by the user's home directory. The path to
the home directory is obtained from environment
variables. On Windows, the USERPROFILE environment
variable is used, falling back to the HOME environment
variable if USERPROFILE is not defined. On all other
platforms, only HOME is used.
Changed in version 3.28: All symlinks are resolved before
collapsing ../ components. See policy CMP0152 <#
policy:CMP0152>.
file(RELATIVE_PATH <variable> <directory> <file>)
Compute the relative path from a <directory> to a <file> and
store it in the <variable>.
file(TO_CMAKE_PATH "<path>" <variable>)
file(TO_NATIVE_PATH "<path>" <variable>)
The TO_CMAKE_PATH mode converts a native <path> into a
cmake-style path with forward-slashes (/). The input can be a
single path or a system search path like $ENV{PATH}. A search
path will be converted to a cmake-style list separated by ;
characters.
The TO_NATIVE_PATH mode converts a cmake-style <path> into a
native path with platform-specific slashes (\ on Windows hosts
and / elsewhere).
Always use double quotes around the <path> to be sure it is
treated as a single argument to this command.
Transfer
file(DOWNLOAD <url> [<file>] <options>...)
file(UPLOAD <file> <url> <options>...)
The DOWNLOAD subcommand downloads the given <url> to a local
<file>. The UPLOAD mode uploads a local <file> to a given
<url>.
Added in version 3.19: If <file> is not specified for
file(DOWNLOAD), the file is not saved. This can be useful if you
want to know if a file can be downloaded (for example, to check
that it exists) without actually saving it anywhere.
Options to both DOWNLOAD and UPLOAD are:
INACTIVITY_TIMEOUT <seconds>
Terminate the operation after a period of inactivity.
LOG <variable>
Store a human-readable log of the operation in a
variable.
SHOW_PROGRESS
Print progress information as status messages until
the operation is complete.
STATUS <variable>
Store the resulting status of the operation in a
variable. The status is a ; separated list of length
2. The first element is the numeric return value for
the operation, and the second element is a string
value for the error. A 0 numeric error means no error
in the operation.
TIMEOUT <seconds>
Terminate the operation after a given total time has
elapsed.
USERPWD <username>:<password>
Added in version 3.7.
Set username and password for operation.
HTTPHEADER <HTTP-header>
Added in version 3.7.
HTTP header for DOWNLOAD and UPLOAD operations.
HTTPHEADER can be repeated for multiple options:
file(DOWNLOAD <url>
HTTPHEADER "Authorization: Bearer <auth-token>"
HTTPHEADER "UserAgent: Mozilla/5.0")
NETRC <level>
Added in version 3.11.
Specify whether the .netrc file is to be used for
operation. If this option is not specified, the value
of the CMAKE_NETRC <#variable:CMAKE_NETRC> variable
will be used instead.
Valid levels are:
IGNORED
The .netrc file is ignored. This is the
default.
OPTIONAL
The .netrc file is optional, and information
in the URL is preferred. The file will be
scanned to find which ever information is
not specified in the URL.
REQUIRED
The .netrc file is required, and information
in the URL is ignored.
NETRC_FILE <file>
Added in version 3.11.
Specify an alternative .netrc file to the one in your
home directory, if the NETRC level is OPTIONAL or
REQUIRED. If this option is not specified, the value
of the CMAKE_NETRC_FILE <#variable:CMAKE_NETRC_FILE>
variable will be used instead.
TLS_VERSION <min>
Added in version 3.30.
Specify minimum TLS version for https:// URLs. If
this option is not specified, the value of the
CMAKE_TLS_VERSION <#variable:CMAKE_TLS_VERSION>
variable or CMAKE_TLS_VERSION <#
envvar:CMAKE_TLS_VERSION> environment variable will be
used instead. See CMAKE_TLS_VERSION <#
variable:CMAKE_TLS_VERSION> for allowed values.
Changed in version 3.31: The default is TLS 1.2.
Previously, no minimum version was enforced by
default.
TLS_VERIFY <ON|OFF>
Specify whether to verify the server certificate for
https:// URLs. If this option is not specified, the
value of the CMAKE_TLS_VERIFY <#
variable:CMAKE_TLS_VERIFY> variable or
CMAKE_TLS_VERIFY <#envvar:CMAKE_TLS_VERIFY>
environment variable will be used instead. If neither
is set, the default is on.
Changed in version 3.31: The default is on.
Previously, the default was off. Users may set the
CMAKE_TLS_VERIFY <#envvar:CMAKE_TLS_VERIFY>
environment variable to 0 to restore the old default.
Added in version 3.18: Added support to file(UPLOAD).
TLS_CAINFO <file>
Specify a custom Certificate Authority file for
https:// URLs. If this option is not specified, the
value of the CMAKE_TLS_CAINFO <#
variable:CMAKE_TLS_CAINFO> variable will be used
instead.
Added in version 3.18: Added support to file(UPLOAD).
For https:// URLs CMake must be built with SSL/TLS support.
Additional options to DOWNLOAD are:
EXPECTED_HASH <algorithm>=<value>
Verify that the downloaded content hash matches the
expected value, where <algorithm> is one of the
algorithms supported by <HASH>. If the file already
exists and matches the hash, the download is skipped.
If the file already exists and does not match the
hash, the file is downloaded again. If after download
the file does not match the hash, the operation fails
with an error. It is an error to specify this option
if DOWNLOAD is not given a <file>.
EXPECTED_MD5 <value>
Historical short-hand for EXPECTED_HASH MD5=<value>.
It is an error to specify this if DOWNLOAD is not
given a <file>.
RANGE_START <value>
Added in version 3.24.
Offset of the start of the range in file in bytes.
Could be omitted to download up to the specified
RANGE_END.
RANGE_END <value>
Added in version 3.24.
Offset of the end of the range in file in bytes. Could
be omitted to download everything from the specified
RANGE_START to the end of file.
Locking
file(LOCK <path> [DIRECTORY] [RELEASE] [GUARD <FUNCTION|FILE|PROCESS>]
[RESULT_VARIABLE <variable>] [TIMEOUT <seconds>])
Added in version 3.2.
Lock a file specified by <path> if no DIRECTORY option present
and file <path>/cmake.lock otherwise. The file will be locked
for the scope defined by the GUARD option (default value is
PROCESS). The RELEASE option can be used to unlock the file
explicitly. If the TIMEOUT option is not specified, CMake will
wait until the lock succeeds or until a fatal error occurs. If
TIMEOUT is set to 0, locking will be tried once and the result
will be reported immediately. If TIMEOUT is not 0, CMake will
try to lock the file for the period specified by the TIMEOUT
<seconds> value. Any errors will be interpreted as fatal if
there is no RESULT_VARIABLE option. Otherwise, the result will
be stored in <variable> and will be 0 on success or an error
message on failure.
Note that lock is advisory; there is no guarantee that other
processes will respect this lock, i.e. lock synchronize two or
more CMake instances sharing some modifiable resources. Similar
logic applies to the DIRECTORY option; locking a parent
directory doesn't prevent other LOCK commands from locking any
child directory or file.
Trying to lock the same file twice is not allowed. Any
intermediate directories and the file itself will be created if
they not exist. The GUARD and TIMEOUT options are ignored on
the RELEASE operation.
Archiving
file(ARCHIVE_CREATE OUTPUT <archive> PATHS <paths>... [FORMAT <format>]
[COMPRESSION <compression> [COMPRESSION_LEVEL <compression-level>]]
[MTIME <mtime>] [WORKING_DIRECTORY <dir>] [VERBOSE])
Added in version 3.18.
Creates the specified <archive> file with the files and
directories listed in <paths>. Note that <paths> must list
actual files or directories; wildcards are not supported.
The options are:
FORMAT <format>
Specify the archive format. Supported values for
<format> are 7zip, gnutar, pax, paxr, raw and zip. If
FORMAT is not given, the default format is paxr.
COMPRESSION <compression>
Some archive formats allow the type of compression to be
specified. The 7zip and zip archive formats already
imply a specific type of compression. The other formats
use no compression by default, but can be directed to do
so with the COMPRESSION option. Valid values for
<compression> are None, BZip2, GZip, XZ, and Zstd.
Note:
With FORMAT set to raw, only one file will be
compressed with the compression type specified by
COMPRESSION.
COMPRESSION_LEVEL <compression-level>
Added in version 3.19.
The compression level can be specified with the
COMPRESSION_LEVEL option. The <compression-level> should
be between 0-9, with the default being 0. The
COMPRESSION option must be present when COMPRESSION_LEVEL
is given.
Added in version 3.26: The <compression-level> of the
Zstd algorithm can be set between 0-19.
MTIME <mtime>
Specify the modification time recorded in tarball
entries.
WORKING_DIRECTORY <dir>
Added in version 3.31.
Specify the directory in which the archive creation
operation will be executed. Paths in the <paths>
argument can be relative to this directory. If this
option is not provided, the current working directory
will be used by default.
VERBOSE
Enable verbose output from the archive operation.
file(ARCHIVE_EXTRACT INPUT <archive> [DESTINATION <dir>]
[PATTERNS <pattern>...] [LIST_ONLY] [VERBOSE] [TOUCH])
Added in version 3.18.
Extracts or lists the content of the specified <archive>.
The options are:
DESTINATION <dir>
Specify the directory under which the content of the
archive will be extracted. If the directory does not
exist, it will be created. If DESTINATION is not given,
the current binary directory will be used.
PATTERNS <pattern>...
Extract/list only files and directories that match one of
the given patterns. Wildcards are supported. If the
PATTERNS option is not given, the entire archive will be
listed or extracted.
LIST_ONLY
List the files in the archive rather than extract them.
TOUCH Added in version 3.24.
Give extracted files a current local timestamp instead of
extracting file timestamps from the archive.
VERBOSE
Enable verbose output from the extraction operation.
Note:
The working directory for this subcommand is the DESTINATION
directory (provided or computed) except when LIST_ONLY is
specified. Therefore, outside of script mode, it may be best
to provide absolute paths to INPUT archives as they are
unlikely to be extracted where a relative path works.
Handling Runtime Binaries
file(GET_RUNTIME_DEPENDENCIES [...])
Added in version 3.16.
Recursively get the list of libraries depended on by the given
files:
file(GET_RUNTIME_DEPENDENCIES
[RESOLVED_DEPENDENCIES_VAR <deps_var>]
[UNRESOLVED_DEPENDENCIES_VAR <unresolved_deps_var>]
[CONFLICTING_DEPENDENCIES_PREFIX <conflicting_deps_prefix>]
[EXECUTABLES <executable_files>...]
[LIBRARIES <library_files>...]
[MODULES <module_files>...]
[DIRECTORIES <directories>...]
[BUNDLE_EXECUTABLE <bundle_executable_file>]
[PRE_INCLUDE_REGEXES <regexes>...]
[PRE_EXCLUDE_REGEXES <regexes>...]
[POST_INCLUDE_REGEXES <regexes>...]
[POST_EXCLUDE_REGEXES <regexes>...]
[POST_INCLUDE_FILES <files>...]
[POST_EXCLUDE_FILES <files>...]
)
Please note that this sub-command is not intended to be used in
project mode. It is intended for use at install time, either
from code generated by the install(RUNTIME_DEPENDENCY_SET) <#
runtime-dependency-set> command, or from code provided by the
project via install(CODE) <#code> or install(SCRIPT) <#script>.
For example:
install(CODE [[
file(GET_RUNTIME_DEPENDENCIES
# ...
)
]])
The arguments are as follows:
RESOLVED_DEPENDENCIES_VAR <deps_var>
Name of the variable in which to store the list of
resolved dependencies.
UNRESOLVED_DEPENDENCIES_VAR <unresolved_deps_var>
Name of the variable in which to store the list of
unresolved dependencies. If this variable is not
specified, and there are any unresolved dependencies,
an error is issued.
CONFLICTING_DEPENDENCIES_PREFIX <conflicting_deps_prefix>
Variable prefix in which to store conflicting
dependency information. Dependencies are conflicting
if two files with the same name are found in two
different directories. The list of filenames that
conflict are stored in
<conflicting_deps_prefix>_FILENAMES. For each
filename, the list of paths that were found for that
filename are stored in
<conflicting_deps_prefix>_<filename>.
EXECUTABLES <executable_files>...
List of executable files to read for dependencies.
These are executables that are typically created with
add_executable() <#command:add_executable>, but they
do not have to be created by CMake. On Apple
platforms, the paths to these files determine the
value of @executable_path when recursively resolving
the libraries. Specifying any kind of library (STATIC,
MODULE, or SHARED) here will result in undefined
behavior.
LIBRARIES <library_files>...
List of library files to read for dependencies. These
are libraries that are typically created with
add_library(SHARED) <#command:add_library>, but they
do not have to be created by CMake. Specifying STATIC
libraries, MODULE libraries, or executables here will
result in undefined behavior.
MODULES <module_files>...
List of loadable module files to read for
dependencies. These are modules that are typically
created with add_library(MODULE) <#
command:add_library>, but they do not have to be
created by CMake. They are typically used by calling
dlopen() at runtime rather than linked at link time
with ld -l. Specifying STATIC libraries, SHARED
libraries, or executables here will result in
undefined behavior.
DIRECTORIES <directories>...
List of additional directories to search for
dependencies. On Linux platforms, these directories
are searched if the dependency is not found in any of
the other usual paths. If it is found in such a
directory, a warning is issued, because it means that
the file is incomplete (it does not list all of the
directories that contain its dependencies). On
Windows platforms, these directories are searched if
the dependency is not found in any of the other search
paths, but no warning is issued, because searching
other paths is a normal part of Windows dependency
resolution. On Apple platforms, this argument has no
effect.
BUNDLE_EXECUTABLE <bundle_executable_file>
Executable to treat as the "bundle executable" when
resolving libraries. On Apple platforms, this
argument determines the value of @executable_path when
recursively resolving libraries for LIBRARIES and
MODULES files. It has no effect on EXECUTABLES files.
On other platforms, it has no effect. This is
typically (but not always) one of the executables in
the EXECUTABLES argument which designates the "main"
executable of the package.
The following arguments specify filters for including or
excluding libraries to be resolved. See below for a full
description of how they work.
PRE_INCLUDE_REGEXES <regexes>...
List of pre-include regexes through which to filter
the names of not-yet-resolved dependencies.
PRE_EXCLUDE_REGEXES <regexes>...
List of pre-exclude regexes through which to filter
the names of not-yet-resolved dependencies.
POST_INCLUDE_REGEXES <regexes>...
List of post-include regexes through which to filter
the names of resolved dependencies.
POST_EXCLUDE_REGEXES <regexes>...
List of post-exclude regexes through which to filter
the names of resolved dependencies.
POST_INCLUDE_FILES <files>...
Added in version 3.21.
List of post-include filenames through which to filter
the names of resolved dependencies. Symlinks are
resolved when attempting to match these filenames.
POST_EXCLUDE_FILES <files>...
Added in version 3.21.
List of post-exclude filenames through which to filter
the names of resolved dependencies. Symlinks are
resolved when attempting to match these filenames.
These arguments can be used to exclude unwanted system libraries
when resolving the dependencies, or to include libraries from a
specific directory. The filtering works as follows:
1. If the not-yet-resolved dependency matches any of the
PRE_INCLUDE_REGEXES, steps 2 and 3 are skipped, and the
dependency resolution proceeds to step 4.
2. If the not-yet-resolved dependency matches any of the
PRE_EXCLUDE_REGEXES, dependency resolution stops for that
dependency.
3. Otherwise, dependency resolution proceeds.
4. file(GET_RUNTIME_DEPENDENCIES) searches for the dependency
according to the linking rules of the platform (see below).
5. If the dependency is found, and its full path matches one of
the POST_INCLUDE_REGEXES or POST_INCLUDE_FILES, the full path
is added to the resolved dependencies, and
file(GET_RUNTIME_DEPENDENCIES) recursively resolves that
library's own dependencies. Otherwise, resolution proceeds to
step 6.
6. If the dependency is found, but its full path matches one of
the POST_EXCLUDE_REGEXES or POST_EXCLUDE_FILES, it is not
added to the resolved dependencies, and dependency resolution
stops for that dependency.
7. If the dependency is found, and its full path does not match
either POST_INCLUDE_REGEXES, POST_INCLUDE_FILES,
POST_EXCLUDE_REGEXES, or POST_EXCLUDE_FILES, the full path is
added to the resolved dependencies, and
file(GET_RUNTIME_DEPENDENCIES) recursively resolves that
library's own dependencies.
Different platforms have different rules for how dependencies
are resolved. These specifics are described here.
On Linux platforms, library resolution works as follows:
1. If the depending file does not have any RUNPATH entries, and
the library exists in one of the depending file's RPATH
entries, or its parents', in that order, the dependency is
resolved to that file.
2. Otherwise, if the depending file has any RUNPATH entries, and
the library exists in one of those entries, the dependency is
resolved to that file.
3. Otherwise, if the library exists in one of the directories
listed by ldconfig, the dependency is resolved to that file.
4. Otherwise, if the library exists in one of the DIRECTORIES
entries, the dependency is resolved to that file. In this
case, a warning is issued, because finding a file in one of
the DIRECTORIES means that the depending file is not complete
(it does not list all the directories from which it pulls
dependencies).
5. Otherwise, the dependency is unresolved.
Changed in version 3.31: Resolution of each encountered library
file name occurs at most once while processing a given root ELF
file (executable or shared object). If a library file name is
encountered again in the dependency tree, the original
resolution is assumed. This behavior more closely matches the
dynamic loader's behavior on Linux.
On Windows platforms, library resolution works as follows:
1. DLL dependency names are converted to lowercase for matching
filters. Windows DLL names are case-insensitive, and some
linkers mangle the case of the DLL dependency names.
However, this makes it more difficult for
PRE_INCLUDE_REGEXES, PRE_EXCLUDE_REGEXES,
POST_INCLUDE_REGEXES, and POST_EXCLUDE_REGEXES to properly
filter DLL names - every regex would have to check for both
uppercase and lowercase letters. For example:
file(GET_RUNTIME_DEPENDENCIES
# ...
PRE_INCLUDE_REGEXES "^[Mm][Yy][Ll][Ii][Bb][Rr][Aa][Rr][Yy]\\.[Dd][Ll][Ll]$"
)
Converting the DLL name to lowercase allows the regexes to
only match lowercase names, thus simplifying the regex. For
example:
file(GET_RUNTIME_DEPENDENCIES
# ...
PRE_INCLUDE_REGEXES "^mylibrary\\.dll$"
)
This regex will match mylibrary.dll regardless of how it is
cased, either on disk or in the depending file. (For example,
it will match mylibrary.dll, MyLibrary.dll, and
MYLIBRARY.DLL.)
Changed in version 3.27: The conversion to lowercase only
applies while matching filters. Results reported after
filtering case-preserve each DLL name as it is found on disk,
if resolved, and otherwise as it is referenced by the
dependent binary.
Prior to CMake 3.27, the results were reported with lowercase
DLL file names, but the directory portion retained its
casing.
2. (Not yet implemented) If the depending file is a Windows
Store app, and the dependency is listed as a dependency in
the application's package manifest, the dependency is
resolved to that file.
3. Otherwise, if the library exists in the same directory as the
depending file, the dependency is resolved to that file.
4. Otherwise, if the library exists in either the operating
system's system32 directory or the Windows directory, in that
order, the dependency is resolved to that file.
5. Otherwise, if the library exists in one of the directories
specified by DIRECTORIES, in the order they are listed, the
dependency is resolved to that file. In this case, a warning
is not issued, because searching other directories is a
normal part of Windows library resolution.
6. Otherwise, the dependency is unresolved.
On Apple platforms, library resolution works as follows:
1. If the dependency starts with @executable_path/, and an
EXECUTABLES argument is in the process of being resolved, and
replacing @executable_path/ with the directory of the
executable yields an existing file, the dependency is
resolved to that file.
2. Otherwise, if the dependency starts with @executable_path/,
and there is a BUNDLE_EXECUTABLE argument, and replacing
@executable_path/ with the directory of the bundle executable
yields an existing file, the dependency is resolved to that
file.
3. Otherwise, if the dependency starts with @loader_path/, and
replacing @loader_path/ with the directory of the depending
file yields an existing file, the dependency is resolved to
that file.
4. Otherwise, if the dependency starts with @rpath/, and
replacing @rpath/ with one of the RPATH entries of the
depending file yields an existing file, the dependency is
resolved to that file. Note that RPATH entries that start
with @executable_path/ or @loader_path/ also have these items
replaced with the appropriate path.
5. Otherwise, if the dependency is an absolute file that exists,
the dependency is resolved to that file.
6. Otherwise, the dependency is unresolved.
This function accepts several variables that determine which
tool is used for dependency resolution:
CMAKE_GET_RUNTIME_DEPENDENCIES_PLATFORM
Determines which operating system and executable format
the files are built for. This could be one of several
values:
o linux+elf
o windows+pe
o macos+macho
If this variable is not specified, it is determined
automatically by system introspection.
CMAKE_GET_RUNTIME_DEPENDENCIES_TOOL
Determines the tool to use for dependency resolution. It
could be one of several values, depending on the value of
CMAKE_GET_RUNTIME_DEPENDENCIES_PLATFORM:
+----------------------------------------+-------------------------------------+
|CMAKE_GET_RUNTIME_DEPENDENCIES_PLATFORM | CMAKE_GET_RUNTIME_DEPENDENCIES_TOOL |
+----------------------------------------+-------------------------------------+
|linux+elf | objdump |
+----------------------------------------+-------------------------------------+
|windows+pe | objdump or dumpbin |
+----------------------------------------+-------------------------------------+
|macos+macho | otool |
+----------------------------------------+-------------------------------------+
If this variable is not specified, it is determined
automatically by system introspection.
CMAKE_GET_RUNTIME_DEPENDENCIES_COMMAND
Determines the path to the tool to use for dependency
resolution. This is the actual path to objdump, dumpbin,
or otool.
If this variable is not specified, it is determined by
the value of CMAKE_OBJDUMP if set, else by system
introspection.
Added in version 3.18: Use CMAKE_OBJDUMP if set.
find_file
A short-hand signature is:
find_file (<VAR> name1 [path1 path2 ...])
The general signature is:
find_file (
<VAR>
name | NAMES name1 [name2 ...]
[HINTS [path | ENV var]... ]
[PATHS [path | ENV var]... ]
[REGISTRY_VIEW (64|32|64_32|32_64|HOST|TARGET|BOTH)]
[PATH_SUFFIXES suffix1 [suffix2 ...]]
[VALIDATOR function]
[DOC "cache documentation string"]
[NO_CACHE]
[REQUIRED]
[NO_DEFAULT_PATH]
[NO_PACKAGE_ROOT_PATH]
[NO_CMAKE_PATH]
[NO_CMAKE_ENVIRONMENT_PATH]
[NO_SYSTEM_ENVIRONMENT_PATH]
[NO_CMAKE_SYSTEM_PATH]
[NO_CMAKE_INSTALL_PREFIX]
[CMAKE_FIND_ROOT_PATH_BOTH |
ONLY_CMAKE_FIND_ROOT_PATH |
NO_CMAKE_FIND_ROOT_PATH]
)
This command is used to find a full path to named file. A cache entry,
or a normal variable if NO_CACHE is specified, named by <VAR> is
created to store the result of this command. If the full path to a
file is found the result is stored in the variable and the search will
not be repeated unless the variable is cleared. If nothing is found,
the result will be <VAR>-NOTFOUND.
Options include:
NAMES Specify one or more possible names for the full path to a file.
When using this to specify names with and without a version
suffix, we recommend specifying the unversioned name first so
that locally-built packages can be found before those provided
by distributions.
HINTS, PATHS
Specify directories to search in addition to the default
locations. The ENV var sub-option reads paths from a system
environment variable.
Changed in version 3.24: On Windows platform, it is possible to
include registry queries as part of the directories, using a
dedicated syntax <#find-using-windows-registry>. Such
specifications will be ignored on all other platforms.
REGISTRY_VIEW
Added in version 3.24.
Specify which registry views must be queried. This option is
only meaningful on Windows platforms and will be ignored on
other ones. When not specified, the TARGET view is used when the
CMP0134 <#policy:CMP0134> policy is NEW. Refer to CMP0134 <#
policy:CMP0134> for the default view when the policy is OLD.
64 Query the 64-bit registry. On 32-bit Windows, it always
returns the string /REGISTRY-NOTFOUND.
32 Query the 32-bit registry.
64_32 Query both views (64 and 32) and generate a path for
each.
32_64 Query both views (32 and 64) and generate a path for
each.
HOST Query the registry matching the architecture of the host:
64 on 64-bit Windows and 32 on 32-bit Windows.
TARGET Query the registry matching the architecture specified by
the CMAKE_SIZEOF_VOID_P <#variable:CMAKE_SIZEOF_VOID_P>
variable. If not defined, fall back to HOST view.
BOTH Query both views (32 and 64). The order depends on the
following rules: If the CMAKE_SIZEOF_VOID_P <#
variable:CMAKE_SIZEOF_VOID_P> variable is defined, use
the following view depending on the content of this
variable:
o 8: 64_32
o 4: 32_64
If the CMAKE_SIZEOF_VOID_P <#
variable:CMAKE_SIZEOF_VOID_P> variable is not defined,
rely on the architecture of the host:
o 64-bit: 64_32
o 32-bit: 32
PATH_SUFFIXES
Specify additional subdirectories to check below each directory
location otherwise considered.
VALIDATOR
Added in version 3.25.
Specify a function() <#command:function> to be called for each
candidate item found (a macro() <#command:macro> cannot be
provided, that will result in an error). Two arguments will be
passed to the validator function: the name of a result variable,
and the absolute path to the candidate item. The item will be
accepted and the search will end unless the function sets the
value in the result variable to false in the calling scope. The
result variable will hold a true value when the validator
function is entered.
function(my_check validator_result_var item)
if(NOT item MATCHES ...)
set(${validator_result_var} FALSE PARENT_SCOPE)
endif()
endfunction()
find_file (result NAMES ... VALIDATOR my_check)
Note that if a cached result is used, the search is skipped and
any VALIDATOR is ignored. The cached result is not required to
pass the validation function.
DOC Specify the documentation string for the <VAR> cache entry.
NO_CACHE
Added in version 3.21.
The result of the search will be stored in a normal variable
rather than a cache entry.
Note:
If the variable is already set before the call (as a normal
or cache variable) then the search will not occur.
Warning:
This option should be used with caution because it can
greatly increase the cost of repeated configure steps.
REQUIRED
Added in version 3.18.
Stop processing with an error message if nothing is found,
otherwise the search will be attempted again the next time
find_file is invoked with the same variable.
If NO_DEFAULT_PATH is specified, then no additional paths are added to
the search. If NO_DEFAULT_PATH is not specified, the search process is
as follows:
1. If called from within a find module or any other script loaded by a
call to find_package(<PackageName>) <#command:find_package>, search
prefixes unique to the current package being found. See policy
CMP0074 <#policy:CMP0074>.
Added in version 3.12.
Specifically, search paths specified by the following variables, in
order:
a. <PackageName>_ROOT <#variable:<PackageName>_ROOT> CMake variable,
where <PackageName> is the case-preserved package name.
b. <PACKAGENAME>_ROOT <#variable:<PACKAGENAME>_ROOT> CMake variable,
where <PACKAGENAME> is the upper-cased package name. See policy
CMP0144 <#policy:CMP0144>.
Added in version 3.27.
c. <PackageName>_ROOT <#envvar:<PackageName>_ROOT> environment
variable, where <PackageName> is the case-preserved package name.
d. <PACKAGENAME>_ROOT <#envvar:<PACKAGENAME>_ROOT> environment
variable, where <PACKAGENAME> is the upper-cased package name.
See policy CMP0144 <#policy:CMP0144>.
Added in version 3.27.
The package root variables are maintained as a stack, so if called
from nested find modules or config packages, root paths from the
parent's find module or config package will be searched after paths
from the current module or package. In other words, the search
order would be <CurrentPackage>_ROOT, ENV{<CurrentPackage>_ROOT},
<ParentPackage>_ROOT, ENV{<ParentPackage>_ROOT}, etc. This can be
skipped if NO_PACKAGE_ROOT_PATH is passed or by setting the
CMAKE_FIND_USE_PACKAGE_ROOT_PATH <#
variable:CMAKE_FIND_USE_PACKAGE_ROOT_PATH> to FALSE.
o <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/include
for each <prefix> in the <PackageName>_ROOT <#
variable:<PackageName>_ROOT> CMake variable and the
<PackageName>_ROOT <#envvar:<PackageName>_ROOT> environment
variable if called from within a find module loaded by
find_package(<PackageName>) <#command:find_package>
2. Search paths specified in cmake-specific cache variables. These are
intended to be used on the command line with a -DVAR=value. The
values are interpreted as semicolon-separated lists <#cmake-
language-lists>. This can be skipped if NO_CMAKE_PATH is passed or
by setting the CMAKE_FIND_USE_CMAKE_PATH <#
variable:CMAKE_FIND_USE_CMAKE_PATH> to FALSE.
o <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/include
for each <prefix> in CMAKE_PREFIX_PATH <#
variable:CMAKE_PREFIX_PATH>
o CMAKE_INCLUDE_PATH <#variable:CMAKE_INCLUDE_PATH>
o CMAKE_FRAMEWORK_PATH <#variable:CMAKE_FRAMEWORK_PATH>
3. Search paths specified in cmake-specific environment variables.
These are intended to be set in the user's shell configuration, and
therefore use the host's native path separator (; on Windows and :
on UNIX). This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is
passed or by setting the CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH <#
variable:CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH> to FALSE.
o <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/include
for each <prefix> in CMAKE_PREFIX_PATH <#envvar:CMAKE_PREFIX_PATH>
o CMAKE_INCLUDE_PATH <#envvar:CMAKE_INCLUDE_PATH>
o CMAKE_FRAMEWORK_PATH <#envvar:CMAKE_FRAMEWORK_PATH>
4. Search the paths specified by the HINTS option. These should be
paths computed by system introspection, such as a hint provided by
the location of another item already found. Hard-coded guesses
should be specified with the PATHS option.
5. Search the standard system environment variables. This can be
skipped if NO_SYSTEM_ENVIRONMENT_PATH is passed or by setting the
CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH <#
variable:CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH> to FALSE.
o The directories in INCLUDE and PATH.
On Windows hosts, CMake 3.3 through 3.27 searched additional paths:
<prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/include
for each <prefix>/[s]bin in PATH, and <entry>/include for other
entries in PATH. This behavior was removed by CMake 3.28.
6. Search cmake variables defined in the Platform files for the current
system. The searching of CMAKE_INSTALL_PREFIX and
CMAKE_STAGING_PREFIX can be skipped if NO_CMAKE_INSTALL_PREFIX is
passed or by setting the CMAKE_FIND_USE_INSTALL_PREFIX <#
variable:CMAKE_FIND_USE_INSTALL_PREFIX> to FALSE. All these
locations can be skipped if NO_CMAKE_SYSTEM_PATH is passed or by
setting the CMAKE_FIND_USE_CMAKE_SYSTEM_PATH <#
variable:CMAKE_FIND_USE_CMAKE_SYSTEM_PATH> to FALSE.
o <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/include
for each <prefix> in CMAKE_SYSTEM_PREFIX_PATH <#
variable:CMAKE_SYSTEM_PREFIX_PATH>
o CMAKE_SYSTEM_INCLUDE_PATH <#variable:CMAKE_SYSTEM_INCLUDE_PATH>
o CMAKE_SYSTEM_FRAMEWORK_PATH <#
variable:CMAKE_SYSTEM_FRAMEWORK_PATH>
The platform paths that these variables contain are locations that
typically include installed software. An example being /usr/local
for UNIX based platforms.
7. Search the paths specified by the PATHS option or in the short-hand
version of the command. These are typically hard-coded guesses.
The CMAKE_IGNORE_PATH <#variable:CMAKE_IGNORE_PATH>,
CMAKE_IGNORE_PREFIX_PATH <#variable:CMAKE_IGNORE_PREFIX_PATH>,
CMAKE_SYSTEM_IGNORE_PATH <#variable:CMAKE_SYSTEM_IGNORE_PATH> and
CMAKE_SYSTEM_IGNORE_PREFIX_PATH <#
variable:CMAKE_SYSTEM_IGNORE_PREFIX_PATH> variables can also cause some
of the above locations to be ignored.
Added in version 3.16: Added CMAKE_FIND_USE_<CATEGORY>_PATH variables
to globally disable various search locations.
On macOS the CMAKE_FIND_FRAMEWORK <#variable:CMAKE_FIND_FRAMEWORK> and
CMAKE_FIND_APPBUNDLE <#variable:CMAKE_FIND_APPBUNDLE> variables
determine the order of preference between Apple-style and unix-style
package components.
The CMake variable CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> specifies one or more directories to be
prepended to all other search directories. This effectively "re-roots"
the entire search under given locations. Paths which are descendants
of the CMAKE_STAGING_PREFIX <#variable:CMAKE_STAGING_PREFIX> are
excluded from this re-rooting, because that variable is always a path
on the host system. By default the CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> is empty.
The CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> variable can also be used
to specify exactly one directory to use as a prefix. Setting
CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> also has other effects. See
the documentation for that variable for more.
These variables are especially useful when cross-compiling to point to
the root directory of the target environment and CMake will search
there too. By default at first the directories listed in
CMAKE_FIND_ROOT_PATH <#variable:CMAKE_FIND_ROOT_PATH> are searched,
then the CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> directory is searched,
and then the non-rooted directories will be searched. The default
behavior can be adjusted by setting CMAKE_FIND_ROOT_PATH_MODE_INCLUDE
<#variable:CMAKE_FIND_ROOT_PATH_MODE_INCLUDE>. This behavior can be
manually overridden on a per-call basis using options:
CMAKE_FIND_ROOT_PATH_BOTH
Search in the order described above.
NO_CMAKE_FIND_ROOT_PATH
Do not use the CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> variable.
ONLY_CMAKE_FIND_ROOT_PATH
Search only the re-rooted directories and directories below
CMAKE_STAGING_PREFIX <#variable:CMAKE_STAGING_PREFIX>.
The default search order is designed to be most-specific to
least-specific for common use cases. Projects may override the order
by simply calling the command multiple times and using the NO_*
options:
find_file (<VAR> NAMES name PATHS paths... NO_DEFAULT_PATH)
find_file (<VAR> NAMES name)
Once one of the calls succeeds the result variable will be set and
stored in the cache so that no call will search again.
find_library
A short-hand signature is:
find_library (<VAR> name1 [path1 path2 ...])
The general signature is:
find_library (
<VAR>
name | NAMES name1 [name2 ...] [NAMES_PER_DIR]
[HINTS [path | ENV var]... ]
[PATHS [path | ENV var]... ]
[REGISTRY_VIEW (64|32|64_32|32_64|HOST|TARGET|BOTH)]
[PATH_SUFFIXES suffix1 [suffix2 ...]]
[VALIDATOR function]
[DOC "cache documentation string"]
[NO_CACHE]
[REQUIRED]
[NO_DEFAULT_PATH]
[NO_PACKAGE_ROOT_PATH]
[NO_CMAKE_PATH]
[NO_CMAKE_ENVIRONMENT_PATH]
[NO_SYSTEM_ENVIRONMENT_PATH]
[NO_CMAKE_SYSTEM_PATH]
[NO_CMAKE_INSTALL_PREFIX]
[CMAKE_FIND_ROOT_PATH_BOTH |
ONLY_CMAKE_FIND_ROOT_PATH |
NO_CMAKE_FIND_ROOT_PATH]
)
This command is used to find a library. A cache entry, or a normal
variable if NO_CACHE is specified, named by <VAR> is created to store
the result of this command. If the library is found the result is
stored in the variable and the search will not be repeated unless the
variable is cleared. If nothing is found, the result will be
<VAR>-NOTFOUND.
Options include:
NAMES Specify one or more possible names for the library.
When using this to specify names with and without a version
suffix, we recommend specifying the unversioned name first so
that locally-built packages can be found before those provided
by distributions.
HINTS, PATHS
Specify directories to search in addition to the default
locations. The ENV var sub-option reads paths from a system
environment variable.
Changed in version 3.24: On Windows platform, it is possible to
include registry queries as part of the directories, using a
dedicated syntax <#find-using-windows-registry>. Such
specifications will be ignored on all other platforms.
REGISTRY_VIEW
Added in version 3.24.
Specify which registry views must be queried. This option is
only meaningful on Windows platforms and will be ignored on
other ones. When not specified, the TARGET view is used when the
CMP0134 <#policy:CMP0134> policy is NEW. Refer to CMP0134 <#
policy:CMP0134> for the default view when the policy is OLD.
64 Query the 64-bit registry. On 32-bit Windows, it always
returns the string /REGISTRY-NOTFOUND.
32 Query the 32-bit registry.
64_32 Query both views (64 and 32) and generate a path for
each.
32_64 Query both views (32 and 64) and generate a path for
each.
HOST Query the registry matching the architecture of the host:
64 on 64-bit Windows and 32 on 32-bit Windows.
TARGET Query the registry matching the architecture specified by
the CMAKE_SIZEOF_VOID_P <#variable:CMAKE_SIZEOF_VOID_P>
variable. If not defined, fall back to HOST view.
BOTH Query both views (32 and 64). The order depends on the
following rules: If the CMAKE_SIZEOF_VOID_P <#
variable:CMAKE_SIZEOF_VOID_P> variable is defined, use
the following view depending on the content of this
variable:
o 8: 64_32
o 4: 32_64
If the CMAKE_SIZEOF_VOID_P <#
variable:CMAKE_SIZEOF_VOID_P> variable is not defined,
rely on the architecture of the host:
o 64-bit: 64_32
o 32-bit: 32
PATH_SUFFIXES
Specify additional subdirectories to check below each directory
location otherwise considered.
VALIDATOR
Added in version 3.25.
Specify a function() <#command:function> to be called for each
candidate item found (a macro() <#command:macro> cannot be
provided, that will result in an error). Two arguments will be
passed to the validator function: the name of a result variable,
and the absolute path to the candidate item. The item will be
accepted and the search will end unless the function sets the
value in the result variable to false in the calling scope. The
result variable will hold a true value when the validator
function is entered.
function(my_check validator_result_var item)
if(NOT item MATCHES ...)
set(${validator_result_var} FALSE PARENT_SCOPE)
endif()
endfunction()
find_library (result NAMES ... VALIDATOR my_check)
Note that if a cached result is used, the search is skipped and
any VALIDATOR is ignored. The cached result is not required to
pass the validation function.
DOC Specify the documentation string for the <VAR> cache entry.
NO_CACHE
Added in version 3.21.
The result of the search will be stored in a normal variable
rather than a cache entry.
Note:
If the variable is already set before the call (as a normal
or cache variable) then the search will not occur.
Warning:
This option should be used with caution because it can
greatly increase the cost of repeated configure steps.
REQUIRED
Added in version 3.18.
Stop processing with an error message if nothing is found,
otherwise the search will be attempted again the next time
find_library is invoked with the same variable.
If NO_DEFAULT_PATH is specified, then no additional paths are added to
the search. If NO_DEFAULT_PATH is not specified, the search process is
as follows:
1. If called from within a find module or any other script loaded by a
call to find_package(<PackageName>) <#command:find_package>, search
prefixes unique to the current package being found. See policy
CMP0074 <#policy:CMP0074>.
Added in version 3.12.
Specifically, search paths specified by the following variables, in
order:
a. <PackageName>_ROOT <#variable:<PackageName>_ROOT> CMake variable,
where <PackageName> is the case-preserved package name.
b. <PACKAGENAME>_ROOT <#variable:<PACKAGENAME>_ROOT> CMake variable,
where <PACKAGENAME> is the upper-cased package name. See policy
CMP0144 <#policy:CMP0144>.
Added in version 3.27.
c. <PackageName>_ROOT <#envvar:<PackageName>_ROOT> environment
variable, where <PackageName> is the case-preserved package name.
d. <PACKAGENAME>_ROOT <#envvar:<PACKAGENAME>_ROOT> environment
variable, where <PACKAGENAME> is the upper-cased package name.
See policy CMP0144 <#policy:CMP0144>.
Added in version 3.27.
The package root variables are maintained as a stack, so if called
from nested find modules or config packages, root paths from the
parent's find module or config package will be searched after paths
from the current module or package. In other words, the search
order would be <CurrentPackage>_ROOT, ENV{<CurrentPackage>_ROOT},
<ParentPackage>_ROOT, ENV{<ParentPackage>_ROOT}, etc. This can be
skipped if NO_PACKAGE_ROOT_PATH is passed or by setting the
CMAKE_FIND_USE_PACKAGE_ROOT_PATH <#
variable:CMAKE_FIND_USE_PACKAGE_ROOT_PATH> to FALSE.
o <prefix>/lib/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/lib for
each <prefix> in the <PackageName>_ROOT <#
variable:<PackageName>_ROOT> CMake variable and the
<PackageName>_ROOT <#envvar:<PackageName>_ROOT> environment
variable if called from within a find module loaded by
find_package(<PackageName>) <#command:find_package>
2. Search paths specified in cmake-specific cache variables. These are
intended to be used on the command line with a -DVAR=value. The
values are interpreted as semicolon-separated lists <#cmake-
language-lists>. This can be skipped if NO_CMAKE_PATH is passed or
by setting the CMAKE_FIND_USE_CMAKE_PATH <#
variable:CMAKE_FIND_USE_CMAKE_PATH> to FALSE.
o <prefix>/lib/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/lib for
each <prefix> in CMAKE_PREFIX_PATH <#variable:CMAKE_PREFIX_PATH>
o CMAKE_LIBRARY_PATH <#variable:CMAKE_LIBRARY_PATH>
o CMAKE_FRAMEWORK_PATH <#variable:CMAKE_FRAMEWORK_PATH>
3. Search paths specified in cmake-specific environment variables.
These are intended to be set in the user's shell configuration, and
therefore use the host's native path separator (; on Windows and :
on UNIX). This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is
passed or by setting the CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH <#
variable:CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH> to FALSE.
o <prefix>/lib/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/lib for
each <prefix> in CMAKE_PREFIX_PATH <#envvar:CMAKE_PREFIX_PATH>
o CMAKE_LIBRARY_PATH <#envvar:CMAKE_LIBRARY_PATH>
o CMAKE_FRAMEWORK_PATH <#envvar:CMAKE_FRAMEWORK_PATH>
4. Search the paths specified by the HINTS option. These should be
paths computed by system introspection, such as a hint provided by
the location of another item already found. Hard-coded guesses
should be specified with the PATHS option.
5. Search the standard system environment variables. This can be
skipped if NO_SYSTEM_ENVIRONMENT_PATH is passed or by setting the
CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH <#
variable:CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH> to FALSE.
o The directories in LIB and PATH.
On Windows hosts, CMake 3.3 through 3.27 searched additional paths:
<prefix>/lib/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/lib for
each <prefix>/[s]bin in PATH, and <entry>/lib for other entries in
PATH. This behavior was removed by CMake 3.28.
6. Search cmake variables defined in the Platform files for the current
system. The searching of CMAKE_INSTALL_PREFIX and
CMAKE_STAGING_PREFIX can be skipped if NO_CMAKE_INSTALL_PREFIX is
passed or by setting the CMAKE_FIND_USE_INSTALL_PREFIX <#
variable:CMAKE_FIND_USE_INSTALL_PREFIX> to FALSE. All these
locations can be skipped if NO_CMAKE_SYSTEM_PATH is passed or by
setting the CMAKE_FIND_USE_CMAKE_SYSTEM_PATH <#
variable:CMAKE_FIND_USE_CMAKE_SYSTEM_PATH> to FALSE.
o <prefix>/lib/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/lib for
each <prefix> in CMAKE_SYSTEM_PREFIX_PATH <#
variable:CMAKE_SYSTEM_PREFIX_PATH>
o CMAKE_SYSTEM_LIBRARY_PATH <#variable:CMAKE_SYSTEM_LIBRARY_PATH>
o CMAKE_SYSTEM_FRAMEWORK_PATH <#
variable:CMAKE_SYSTEM_FRAMEWORK_PATH>
The platform paths that these variables contain are locations that
typically include installed software. An example being /usr/local
for UNIX based platforms.
7. Search the paths specified by the PATHS option or in the short-hand
version of the command. These are typically hard-coded guesses.
The CMAKE_IGNORE_PATH <#variable:CMAKE_IGNORE_PATH>,
CMAKE_IGNORE_PREFIX_PATH <#variable:CMAKE_IGNORE_PREFIX_PATH>,
CMAKE_SYSTEM_IGNORE_PATH <#variable:CMAKE_SYSTEM_IGNORE_PATH> and
CMAKE_SYSTEM_IGNORE_PREFIX_PATH <#
variable:CMAKE_SYSTEM_IGNORE_PREFIX_PATH> variables can also cause some
of the above locations to be ignored.
Added in version 3.16: Added CMAKE_FIND_USE_<CATEGORY>_PATH variables
to globally disable various search locations.
On macOS the CMAKE_FIND_FRAMEWORK <#variable:CMAKE_FIND_FRAMEWORK> and
CMAKE_FIND_APPBUNDLE <#variable:CMAKE_FIND_APPBUNDLE> variables
determine the order of preference between Apple-style and unix-style
package components.
The CMake variable CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> specifies one or more directories to be
prepended to all other search directories. This effectively "re-roots"
the entire search under given locations. Paths which are descendants
of the CMAKE_STAGING_PREFIX <#variable:CMAKE_STAGING_PREFIX> are
excluded from this re-rooting, because that variable is always a path
on the host system. By default the CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> is empty.
The CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> variable can also be used
to specify exactly one directory to use as a prefix. Setting
CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> also has other effects. See
the documentation for that variable for more.
These variables are especially useful when cross-compiling to point to
the root directory of the target environment and CMake will search
there too. By default at first the directories listed in
CMAKE_FIND_ROOT_PATH <#variable:CMAKE_FIND_ROOT_PATH> are searched,
then the CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> directory is searched,
and then the non-rooted directories will be searched. The default
behavior can be adjusted by setting CMAKE_FIND_ROOT_PATH_MODE_LIBRARY
<#variable:CMAKE_FIND_ROOT_PATH_MODE_LIBRARY>. This behavior can be
manually overridden on a per-call basis using options:
CMAKE_FIND_ROOT_PATH_BOTH
Search in the order described above.
NO_CMAKE_FIND_ROOT_PATH
Do not use the CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> variable.
ONLY_CMAKE_FIND_ROOT_PATH
Search only the re-rooted directories and directories below
CMAKE_STAGING_PREFIX <#variable:CMAKE_STAGING_PREFIX>.
The default search order is designed to be most-specific to
least-specific for common use cases. Projects may override the order
by simply calling the command multiple times and using the NO_*
options:
find_library (<VAR> NAMES name PATHS paths... NO_DEFAULT_PATH)
find_library (<VAR> NAMES name)
Once one of the calls succeeds the result variable will be set and
stored in the cache so that no call will search again.
When more than one value is given to the NAMES option this command by
default will consider one name at a time and search every directory for
it. The NAMES_PER_DIR option tells this command to consider one
directory at a time and search for all names in it.
Each library name given to the NAMES option is first considered as a
library file name and then considered with platform-specific prefixes
(e.g. lib) and suffixes (e.g. .so). Therefore one may specify library
file names such as libfoo.a directly. This can be used to locate
static libraries on UNIX-like systems.
If the library found is a framework, then <VAR> will be set to the full
path to the framework <fullPath>/A.framework. When a full path to a
framework is used as a library, CMake will use a -framework A, and a
-F<fullPath> to link the framework to the target.
Added in version 3.28: The library found can now be a .xcframework
folder.
If the CMAKE_FIND_LIBRARY_CUSTOM_LIB_SUFFIX <#
variable:CMAKE_FIND_LIBRARY_CUSTOM_LIB_SUFFIX> variable is set all
search paths will be tested as normal, with the suffix appended, and
with all matches of lib/ replaced with
lib${CMAKE_FIND_LIBRARY_CUSTOM_LIB_SUFFIX}/. This variable overrides
the FIND_LIBRARY_USE_LIB32_PATHS <#
prop_gbl:FIND_LIBRARY_USE_LIB32_PATHS>, FIND_LIBRARY_USE_LIBX32_PATHS
<#prop_gbl:FIND_LIBRARY_USE_LIBX32_PATHS>, and
FIND_LIBRARY_USE_LIB64_PATHS <#prop_gbl:FIND_LIBRARY_USE_LIB64_PATHS>
global properties.
If the FIND_LIBRARY_USE_LIB32_PATHS <#
prop_gbl:FIND_LIBRARY_USE_LIB32_PATHS> global property is set all
search paths will be tested as normal, with 32/ appended, and with all
matches of lib/ replaced with lib32/. This property is automatically
set for the platforms that are known to need it if at least one of the
languages supported by the project() <#command:project> command is
enabled.
If the FIND_LIBRARY_USE_LIBX32_PATHS <#
prop_gbl:FIND_LIBRARY_USE_LIBX32_PATHS> global property is set all
search paths will be tested as normal, with x32/ appended, and with all
matches of lib/ replaced with libx32/. This property is automatically
set for the platforms that are known to need it if at least one of the
languages supported by the project() <#command:project> command is
enabled.
If the FIND_LIBRARY_USE_LIB64_PATHS <#
prop_gbl:FIND_LIBRARY_USE_LIB64_PATHS> global property is set all
search paths will be tested as normal, with 64/ appended, and with all
matches of lib/ replaced with lib64/. This property is automatically
set for the platforms that are known to need it if at least one of the
languages supported by the project() <#command:project> command is
enabled.
find_package
Note:
The Using Dependencies Guide <#guide:Using Dependencies Guide>
provides a high-level introduction to this general topic. It
provides a broader overview of where the find_package() command fits
into the bigger picture, including its relationship to the
FetchContent <#module:FetchContent> module. The guide is
recommended pre-reading before moving on to the details below.
Find a package (usually provided by something external to the project),
and load its package-specific details. Calls to this command can also
be intercepted by dependency providers <#dependency-providers>.
Typical Usage
Most calls to find_package() typically have the following form:
find_package(<PackageName> [<version>] [REQUIRED] [COMPONENTS <components>...])
The <PackageName> is the only mandatory argument. The <version> is
often omitted, and REQUIRED should be given if the project cannot be
configured successfully without the package. Some more complicated
packages support components which can be selected with the COMPONENTS
keyword, but most packages don't have that level of complexity.
The above is a reduced form of the basic signature. Where possible,
projects should find packages using this form. This reduces complexity
and maximizes the ways in which the package can be found or provided.
Understanding the basic signature should be enough for general usage of
find_package(). Project maintainers who intend to provide a config
package should understand the bigger picture, as explained in Full
Signature and all subsequent sections on this page.
Search Modes
The command has a few modes by which it searches for packages:
Module mode
In this mode, CMake searches for a file called
Find<PackageName>.cmake, looking first in the locations listed
in the CMAKE_MODULE_PATH <#variable:CMAKE_MODULE_PATH>, then
among the Find Modules <#find-modules> provided by the CMake
installation. If the file is found, it is read and processed by
CMake. It is responsible for finding the package, checking the
version, and producing any needed messages. Some Find modules
provide limited or no support for versioning; check the Find
module's documentation.
The Find<PackageName>.cmake file is not typically provided by
the package itself. Rather, it is normally provided by
something external to the package, such as the operating system,
CMake itself, or even the project from which the find_package()
command was called. Being externally provided, Find Modules <#
find-modules> tend to be heuristic in nature and are susceptible
to becoming out-of-date. They typically search for certain
libraries, files and other package artifacts.
Module mode is only supported by the basic command signature.
Config mode
In this mode, CMake searches for a file called
<lowercasePackageName>-config.cmake or
<PackageName>Config.cmake. It will also look for
<lowercasePackageName>-config-version.cmake or
<PackageName>ConfigVersion.cmake if version details were
specified (see Config Mode Version Selection for an explanation
of how these separate version files are used).
In config mode, the command can be given a list of names to
search for as package names. The locations where CMake searches
for the config and version files is considerably more
complicated than for Module mode (see Config Mode Search
Procedure).
The config and version files are typically installed as part of
the package, so they tend to be more reliable than Find modules.
They usually contain direct knowledge of the package contents,
so no searching or heuristics are needed within the config or
version files themselves.
Config mode is supported by both the basic and full command
signatures.
FetchContent redirection mode
Added in version 3.24: A call to find_package() can be
redirected internally to a package provided by the FetchContent
<#module:FetchContent> module. To the caller, the behavior will
appear similar to Config mode, except that the search logic is
by-passed and the component information is not used. See
FetchContent_Declare() <#command:fetchcontent_declare> and
FetchContent_MakeAvailable() <#
command:fetchcontent_makeavailable> for further details.
When not redirected to a package provided by FetchContent <#
module:FetchContent>, the command arguments determine whether Module or
Config mode is used. When the basic signature is used, the command
searches in Module mode first. If the package is not found, the search
falls back to Config mode. A user may set the
CMAKE_FIND_PACKAGE_PREFER_CONFIG <#
variable:CMAKE_FIND_PACKAGE_PREFER_CONFIG> variable to true to reverse
the priority and direct CMake to search using Config mode first before
falling back to Module mode. The basic signature can also be forced to
use only Module mode with a MODULE keyword. If the full signature is
used, the command only searches in Config mode.
Basic Signature
find_package(<PackageName> [version] [EXACT] [QUIET] [MODULE]
[REQUIRED] [[COMPONENTS] [components...]]
[OPTIONAL_COMPONENTS components...]
[REGISTRY_VIEW (64|32|64_32|32_64|HOST|TARGET|BOTH)]
[GLOBAL]
[NO_POLICY_SCOPE]
[BYPASS_PROVIDER])
The basic signature is supported by both Module and Config modes. The
MODULE keyword implies that only Module mode can be used to find the
package, with no fallback to Config mode.
Regardless of the mode used, a <PackageName>_FOUND variable will be set
to indicate whether the package was found. When the package is found,
package-specific information may be provided through other variables
and Imported Targets <#imported-targets> documented by the package
itself. The QUIET option disables informational messages, including
those indicating that the package cannot be found if it is not
REQUIRED. The REQUIRED option stops processing with an error message
if the package cannot be found.
A package-specific list of required components may be listed after the
COMPONENTS keyword. If any of these components are not able to be
satisfied, the package overall is considered to be not found. If the
REQUIRED option is also present, this is treated as a fatal error,
otherwise execution still continues. As a form of shorthand, if the
REQUIRED option is present, the COMPONENTS keyword can be omitted and
the required components can be listed directly after REQUIRED.
Additional optional components may be listed after OPTIONAL_COMPONENTS.
If these cannot be satisfied, the package overall can still be
considered found, as long as all required components are satisfied.
The set of available components and their meaning are defined by the
target package. Formally, it is up to the target package how to
interpret the component information given to it, but it should follow
the expectations stated above. For calls where no components are
specified, there is no single expected behavior and target packages
should clearly define what occurs in such cases. Common arrangements
include assuming it should find all components, no components or some
well-defined subset of the available components.
Added in version 3.24: The REGISTRY_VIEW keyword specifies which
registry views should be queried. This keyword is only meaningful on
Windows platforms and will be ignored on all others. Formally, it is up
to the target package how to interpret the registry view information
given to it.
Added in version 3.24: Specifying the GLOBAL keyword will promote all
imported targets to a global scope in the importing project.
Alternatively, this functionality can be enabled by setting the
CMAKE_FIND_PACKAGE_TARGETS_GLOBAL <#
variable:CMAKE_FIND_PACKAGE_TARGETS_GLOBAL> variable.
The [version] argument requests a version with which the package found
should be compatible. There are two possible forms in which it may be
specified:
o A single version with the format major[.minor[.patch[.tweak]]],
where each component is a numeric value.
o A version range with the format versionMin...[<]versionMax where
versionMin and versionMax have the same format and constraints on
components being integers as the single version. By default, both
end points are included. By specifying <, the upper end point
will be excluded. Version ranges are only supported with CMake
3.19 or later.
The EXACT option requests that the version be matched exactly. This
option is incompatible with the specification of a version range.
If no [version] and/or component list is given to a recursive
invocation inside a find-module, the corresponding arguments are
forwarded automatically from the outer call (including the EXACT flag
for [version]). Version support is currently provided only on a
package-by-package basis (see the Version Selection section below).
When a version range is specified but the package is only designed to
expect a single version, the package will ignore the upper end point of
the range and only take the single version at the lower end of the
range into account.
See the cmake_policy() <#command:cmake_policy> command documentation
for discussion of the NO_POLICY_SCOPE option.
Added in version 3.24: The BYPASS_PROVIDER keyword is only allowed when
find_package() is being called by a dependency provider <#dependency-
providers>. It can be used by providers to call the built-in
find_package() implementation directly and prevent that call from being
re-routed back to itself. Future versions of CMake may detect attempts
to use this keyword from places other than a dependency provider and
halt with a fatal error.
Full Signature
find_package(<PackageName> [version] [EXACT] [QUIET]
[REQUIRED] [[COMPONENTS] [components...]]
[OPTIONAL_COMPONENTS components...]
[CONFIG|NO_MODULE]
[GLOBAL]
[NO_POLICY_SCOPE]
[BYPASS_PROVIDER]
[NAMES name1 [name2 ...]]
[CONFIGS config1 [config2 ...]]
[HINTS path1 [path2 ... ]]
[PATHS path1 [path2 ... ]]
[REGISTRY_VIEW (64|32|64_32|32_64|HOST|TARGET|BOTH)]
[PATH_SUFFIXES suffix1 [suffix2 ...]]
[NO_DEFAULT_PATH]
[NO_PACKAGE_ROOT_PATH]
[NO_CMAKE_PATH]
[NO_CMAKE_ENVIRONMENT_PATH]
[NO_SYSTEM_ENVIRONMENT_PATH]
[NO_CMAKE_PACKAGE_REGISTRY]
[NO_CMAKE_BUILDS_PATH] # Deprecated; does nothing.
[NO_CMAKE_SYSTEM_PATH]
[NO_CMAKE_INSTALL_PREFIX]
[NO_CMAKE_SYSTEM_PACKAGE_REGISTRY]
[CMAKE_FIND_ROOT_PATH_BOTH |
ONLY_CMAKE_FIND_ROOT_PATH |
NO_CMAKE_FIND_ROOT_PATH])
The CONFIG option, the synonymous NO_MODULE option, or the use of
options not specified in the basic signature all enforce pure Config
mode. In pure Config mode, the command skips Module mode search and
proceeds at once with Config mode search.
Config mode search attempts to locate a configuration file provided by
the package to be found. A cache entry called <PackageName>_DIR is
created to hold the directory containing the file. By default, the
command searches for a package with the name <PackageName>. If the
NAMES option is given, the names following it are used instead of
<PackageName>. The names are also considered when determining whether
to redirect the call to a package provided by FetchContent <#
module:FetchContent>.
The command searches for a file called <PackageName>Config.cmake or
<lowercasePackageName>-config.cmake for each name specified. A
replacement set of possible configuration file names may be given using
the CONFIGS option. The Config Mode Search Procedure is specified
below. Once found, any version constraint is checked, and if
satisfied, the configuration file is read and processed by CMake.
Since the file is provided by the package it already knows the location
of package contents. The full path to the configuration file is stored
in the cmake variable <PackageName>_CONFIG.
All configuration files which have been considered by CMake while
searching for the package with an appropriate version are stored in the
<PackageName>_CONSIDERED_CONFIGS variable, and the associated versions
in the <PackageName>_CONSIDERED_VERSIONS variable.
If the package configuration file cannot be found CMake will generate
an error describing the problem unless the QUIET argument is specified.
If REQUIRED is specified and the package is not found a fatal error is
generated and the configure step stops executing. If <PackageName>_DIR
has been set to a directory not containing a configuration file CMake
will ignore it and search from scratch.
Package maintainers providing CMake package configuration files are
encouraged to name and install them such that the Config Mode Search
Procedure outlined below will find them without requiring use of
additional options.
Config Mode Search Procedure
Note:
When Config mode is used, this search procedure is applied
regardless of whether the full or basic signature was given.
Added in version 3.24: All calls to find_package() (even in Module
mode) first look for a config package file in the
CMAKE_FIND_PACKAGE_REDIRECTS_DIR <#
variable:CMAKE_FIND_PACKAGE_REDIRECTS_DIR> directory. The FetchContent
<#module:FetchContent> module, or even the project itself, may write
files to that location to redirect find_package() calls to content
already provided by the project. If no config package file is found in
that location, the search proceeds with the logic described below.
CMake constructs a set of possible installation prefixes for the
package. Under each prefix several directories are searched for a
configuration file. The tables below show the directories searched.
Each entry is meant for installation trees following Windows (W), UNIX
(U), or Apple (A) conventions:
+----------------------------------------------------------------+------------+
|Entry | Convention |
+----------------------------------------------------------------+------------+
|<prefix>/ | W |
+----------------------------------------------------------------+------------+
|<prefix>/(cmake|CMake)/ | W |
+----------------------------------------------------------------+------------+
|<prefix>/<name>*/ | W |
+----------------------------------------------------------------+------------+
|<prefix>/<name>*/(cmake|CMake)/ | W |
+----------------------------------------------------------------+------------+
|<prefix>/<name>*/(cmake|CMake)/<name>*/ [1] | W |
+----------------------------------------------------------------+------------+
|<prefix>/(lib/<arch>|lib*|share)/cmake/<name>*/ | U |
+----------------------------------------------------------------+------------+
|<prefix>/(lib/<arch>|lib*|share)/<name>*/ | U |
+----------------------------------------------------------------+------------+
|<prefix>/(lib/<arch>|lib*|share)/<name>*/(cmake|CMake)/ | U |
+----------------------------------------------------------------+------------+
|<prefix>/<name>*/(lib/<arch>|lib*|share)/cmake/<name>*/ | W/U |
+----------------------------------------------------------------+------------+
|<prefix>/<name>*/(lib/<arch>|lib*|share)/<name>*/ | W/U |
+----------------------------------------------------------------+------------+
|<prefix>/<name>*/(lib/<arch>|lib*|share)/<name>*/(cmake|CMake)/ | W/U |
+----------------------------------------------------------------+------------+
[1] Added in version 3.25.
On systems supporting macOS FRAMEWORK <#prop_tgt:FRAMEWORK> and
BUNDLE <#prop_tgt:BUNDLE>, the following directories are searched
for Frameworks or Application Bundles containing a configuration
file:
+------------------------------------------------------+------------+
|Entry | Convention |
+------------------------------------------------------+------------+
|<prefix>/<name>.framework/Resources/ | A |
+------------------------------------------------------+------------+
|<prefix>/<name>.framework/Resources/CMake/ | A |
+------------------------------------------------------+------------+
|<prefix>/<name>.framework/Versions/*/Resources/ | A |
+------------------------------------------------------+------------+
|<prefix>/<name>.framework/Versions/*/Resources/CMake/ | A |
+------------------------------------------------------+------------+
|<prefix>/<name>.app/Contents/Resources/ | A |
+------------------------------------------------------+------------+
|<prefix>/<name>.app/Contents/Resources/CMake/ | A |
+------------------------------------------------------+------------+
In all cases the <name> is treated as case-insensitive and
corresponds to any of the names specified (<PackageName> or names
given by NAMES).
If at least one compiled language has been enabled, the
architecture-specific lib/<arch> and lib* directories may be
searched based on the compiler's target architecture, in the
following order:
lib/<arch>
Searched if the CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> variable is set.
lib64 Searched on 64 bit platforms (CMAKE_SIZEOF_VOID_P <#
variable:CMAKE_SIZEOF_VOID_P> is 8) and the
FIND_LIBRARY_USE_LIB64_PATHS <#
prop_gbl:FIND_LIBRARY_USE_LIB64_PATHS> property is set to TRUE.
lib32 Searched on 32 bit platforms (CMAKE_SIZEOF_VOID_P <#
variable:CMAKE_SIZEOF_VOID_P> is 4) and the
FIND_LIBRARY_USE_LIB32_PATHS <#
prop_gbl:FIND_LIBRARY_USE_LIB32_PATHS> property is set to TRUE.
libx32 Searched on platforms using the x32 ABI if the
FIND_LIBRARY_USE_LIBX32_PATHS <#
prop_gbl:FIND_LIBRARY_USE_LIBX32_PATHS> property is set to TRUE.
lib Always searched.
Changed in version 3.24: On Windows platform, it is possible to include
registry queries as part of the directories specified through HINTS and
PATHS keywords, using a dedicated syntax <#find-using-windows-
registry>. Such specifications will be ignored on all other platforms.
Added in version 3.24: REGISTRY_VIEW can be specified to manage Windows
registry queries specified as part of PATHS and HINTS.
Specify which registry views must be queried. This option is only
meaningful on Windows platforms and will be ignored on other ones. When
not specified, the TARGET view is used when the CMP0134 <#
policy:CMP0134> policy is NEW. Refer to CMP0134 <#policy:CMP0134> for
the default view when the policy is OLD.
64 Query the 64-bit registry. On 32-bit Windows, it always returns
the string /REGISTRY-NOTFOUND.
32 Query the 32-bit registry.
64_32 Query both views (64 and 32) and generate a path for each.
32_64 Query both views (32 and 64) and generate a path for each.
HOST Query the registry matching the architecture of the host: 64 on
64-bit Windows and 32 on 32-bit Windows.
TARGET Query the registry matching the architecture specified by the
CMAKE_SIZEOF_VOID_P <#variable:CMAKE_SIZEOF_VOID_P> variable. If
not defined, fall back to HOST view.
BOTH Query both views (32 and 64). The order depends on the following
rules: If the CMAKE_SIZEOF_VOID_P <#
variable:CMAKE_SIZEOF_VOID_P> variable is defined, use the
following view depending on the content of this variable:
o 8: 64_32
o 4: 32_64
If the CMAKE_SIZEOF_VOID_P <#variable:CMAKE_SIZEOF_VOID_P>
variable is not defined, rely on the architecture of the host:
o 64-bit: 64_32
o 32-bit: 32
If PATH_SUFFIXES is specified, the suffixes are appended to each (W) or
(U) directory entry one-by-one.
This set of directories is intended to work in cooperation with
projects that provide configuration files in their installation trees.
Directories above marked with (W) are intended for installations on
Windows where the prefix may point at the top of an application's
installation directory. Those marked with (U) are intended for
installations on UNIX platforms where the prefix is shared by multiple
packages. This is merely a convention, so all (W) and (U) directories
are still searched on all platforms. Directories marked with (A) are
intended for installations on Apple platforms. The
CMAKE_FIND_FRAMEWORK <#variable:CMAKE_FIND_FRAMEWORK> and
CMAKE_FIND_APPBUNDLE <#variable:CMAKE_FIND_APPBUNDLE> variables
determine the order of preference.
The set of installation prefixes is constructed using the following
steps. If NO_DEFAULT_PATH is specified all NO_* options are enabled.
1. Search prefixes unique to the current <PackageName> being found.
See policy CMP0074 <#policy:CMP0074>.
Added in version 3.12.
Specifically, search prefixes specified by the following variables,
in order:
a. <PackageName>_ROOT <#variable:<PackageName>_ROOT> CMake variable,
where <PackageName> is the case-preserved package name.
b. <PACKAGENAME>_ROOT <#variable:<PACKAGENAME>_ROOT> CMake variable,
where <PACKAGENAME> is the upper-cased package name. See policy
CMP0144 <#policy:CMP0144>.
Added in version 3.27.
c. <PackageName>_ROOT <#envvar:<PackageName>_ROOT> environment
variable, where <PackageName> is the case-preserved package name.
d. <PACKAGENAME>_ROOT <#envvar:<PACKAGENAME>_ROOT> environment
variable, where <PACKAGENAME> is the upper-cased package name.
See policy CMP0144 <#policy:CMP0144>.
Added in version 3.27.
The package root variables are maintained as a stack so if called
from within a find module, root paths from the parent's find module
will also be searched after paths for the current package. This can
be skipped if NO_PACKAGE_ROOT_PATH is passed or by setting the
CMAKE_FIND_USE_PACKAGE_ROOT_PATH <#
variable:CMAKE_FIND_USE_PACKAGE_ROOT_PATH> to FALSE.
2. Search paths specified in cmake-specific cache variables. These are
intended to be used on the command line with a -DVAR=VALUE <#
cmdoption-cmake-D>. The values are interpreted as
semicolon-separated lists <#cmake-language-lists>. This can be
skipped if NO_CMAKE_PATH is passed or by setting the
CMAKE_FIND_USE_CMAKE_PATH <#variable:CMAKE_FIND_USE_CMAKE_PATH> to
FALSE:
o CMAKE_PREFIX_PATH <#variable:CMAKE_PREFIX_PATH>
o CMAKE_FRAMEWORK_PATH <#variable:CMAKE_FRAMEWORK_PATH>
o CMAKE_APPBUNDLE_PATH <#variable:CMAKE_APPBUNDLE_PATH>
3. Search paths specified in cmake-specific environment variables.
These are intended to be set in the user's shell configuration, and
therefore use the host's native path separator (; on Windows and :
on UNIX). This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is
passed or by setting the CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH <#
variable:CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH> to FALSE:
o <PackageName>_DIR
o CMAKE_PREFIX_PATH <#envvar:CMAKE_PREFIX_PATH>
o CMAKE_FRAMEWORK_PATH <#envvar:CMAKE_FRAMEWORK_PATH>
o CMAKE_APPBUNDLE_PATH <#envvar:CMAKE_APPBUNDLE_PATH>
4. Search paths specified by the HINTS option. These should be paths
computed by system introspection, such as a hint provided by the
location of another item already found. Hard-coded guesses should
be specified with the PATHS option.
5. Search the standard system environment variables. This can be
skipped if NO_SYSTEM_ENVIRONMENT_PATH is passed or by setting the
CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH <#
variable:CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH> to FALSE. Path
entries ending in /bin or /sbin are automatically converted to their
parent directories:
o PATH
6. Search paths stored in the CMake User Package Registry <#user-
package-registry>. This can be skipped if NO_CMAKE_PACKAGE_REGISTRY
is passed or by setting the variable CMAKE_FIND_USE_PACKAGE_REGISTRY
<#variable:CMAKE_FIND_USE_PACKAGE_REGISTRY> to FALSE or the
deprecated variable CMAKE_FIND_PACKAGE_NO_PACKAGE_REGISTRY <#
variable:CMAKE_FIND_PACKAGE_NO_PACKAGE_REGISTRY> to TRUE.
See the cmake-packages(7) <#manual:cmake-packages(7)> manual for
details on the user package registry.
7. Search cmake variables defined in the Platform files for the current
system. The searching of CMAKE_INSTALL_PREFIX <#
variable:CMAKE_INSTALL_PREFIX> and CMAKE_STAGING_PREFIX <#
variable:CMAKE_STAGING_PREFIX> can be skipped if
NO_CMAKE_INSTALL_PREFIX is passed or by setting the
CMAKE_FIND_USE_INSTALL_PREFIX <#
variable:CMAKE_FIND_USE_INSTALL_PREFIX> to FALSE. All these
locations can be skipped if NO_CMAKE_SYSTEM_PATH is passed or by
setting the CMAKE_FIND_USE_CMAKE_SYSTEM_PATH <#
variable:CMAKE_FIND_USE_CMAKE_SYSTEM_PATH> to FALSE:
o CMAKE_SYSTEM_PREFIX_PATH <#variable:CMAKE_SYSTEM_PREFIX_PATH>
o CMAKE_SYSTEM_FRAMEWORK_PATH <#
variable:CMAKE_SYSTEM_FRAMEWORK_PATH>
o CMAKE_SYSTEM_APPBUNDLE_PATH <#
variable:CMAKE_SYSTEM_APPBUNDLE_PATH>
The platform paths that these variables contain are locations that
typically include installed software. An example being /usr/local
for UNIX based platforms.
8. Search paths stored in the CMake System Package Registry <#system-
package-registry>. This can be skipped if
NO_CMAKE_SYSTEM_PACKAGE_REGISTRY is passed or by setting the
CMAKE_FIND_USE_SYSTEM_PACKAGE_REGISTRY <#
variable:CMAKE_FIND_USE_SYSTEM_PACKAGE_REGISTRY> variable to FALSE
or the deprecated variable
CMAKE_FIND_PACKAGE_NO_SYSTEM_PACKAGE_REGISTRY <#
variable:CMAKE_FIND_PACKAGE_NO_SYSTEM_PACKAGE_REGISTRY> to TRUE.
See the cmake-packages(7) <#manual:cmake-packages(7)> manual for
details on the system package registry.
9. Search paths specified by the PATHS option. These are typically
hard-coded guesses.
The CMAKE_IGNORE_PATH <#variable:CMAKE_IGNORE_PATH>,
CMAKE_IGNORE_PREFIX_PATH <#variable:CMAKE_IGNORE_PREFIX_PATH>,
CMAKE_SYSTEM_IGNORE_PATH <#variable:CMAKE_SYSTEM_IGNORE_PATH> and
CMAKE_SYSTEM_IGNORE_PREFIX_PATH <#
variable:CMAKE_SYSTEM_IGNORE_PREFIX_PATH> variables can also cause some
of the above locations to be ignored.
Paths are searched in the order described above. The first viable
package configuration file found is used, even if a newer version of
the package resides later in the list of search paths.
For search paths which contain <name>*, the order among matching paths
is unspecified unless the CMAKE_FIND_PACKAGE_SORT_ORDER <#
variable:CMAKE_FIND_PACKAGE_SORT_ORDER> variable is set. This
variable, along with the CMAKE_FIND_PACKAGE_SORT_DIRECTION <#
variable:CMAKE_FIND_PACKAGE_SORT_DIRECTION> variable, determines the
order in which CMake considers paths that match a single search path
containing <name>*. For example, if the file system contains the
package configuration files
<prefix>/example-1.2/example-config.cmake
<prefix>/example-1.10/example-config.cmake
<prefix>/share/example-2.0/example-config.cmake
it is unspecified (when the aforementioned variables are unset) whether
find_package(example) will find example-1.2 or example-1.10 (assuming
that both are viable), but find_package will not find example-2.0,
because one of the other two will be found first.
To control the order in which find_package searches directories that
match a glob expression, use CMAKE_FIND_PACKAGE_SORT_ORDER <#
variable:CMAKE_FIND_PACKAGE_SORT_ORDER> and
CMAKE_FIND_PACKAGE_SORT_DIRECTION <#
variable:CMAKE_FIND_PACKAGE_SORT_DIRECTION>. For instance, to cause
the above example to select example-1.10, one can set
SET(CMAKE_FIND_PACKAGE_SORT_ORDER NATURAL)
SET(CMAKE_FIND_PACKAGE_SORT_DIRECTION DEC)
before calling find_package.
Added in version 3.16: Added the CMAKE_FIND_USE_<CATEGORY> variables to
globally disable various search locations.
The CMake variable CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> specifies one or more directories to be
prepended to all other search directories. This effectively "re-roots"
the entire search under given locations. Paths which are descendants
of the CMAKE_STAGING_PREFIX <#variable:CMAKE_STAGING_PREFIX> are
excluded from this re-rooting, because that variable is always a path
on the host system. By default the CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> is empty.
The CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> variable can also be used
to specify exactly one directory to use as a prefix. Setting
CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> also has other effects. See
the documentation for that variable for more.
These variables are especially useful when cross-compiling to point to
the root directory of the target environment and CMake will search
there too. By default at first the directories listed in
CMAKE_FIND_ROOT_PATH <#variable:CMAKE_FIND_ROOT_PATH> are searched,
then the CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> directory is searched,
and then the non-rooted directories will be searched. The default
behavior can be adjusted by setting CMAKE_FIND_ROOT_PATH_MODE_PACKAGE
<#variable:CMAKE_FIND_ROOT_PATH_MODE_PACKAGE>. This behavior can be
manually overridden on a per-call basis using options:
CMAKE_FIND_ROOT_PATH_BOTH
Search in the order described above.
NO_CMAKE_FIND_ROOT_PATH
Do not use the CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> variable.
ONLY_CMAKE_FIND_ROOT_PATH
Search only the re-rooted directories and directories below
CMAKE_STAGING_PREFIX <#variable:CMAKE_STAGING_PREFIX>.
The default search order is designed to be most-specific to
least-specific for common use cases. Projects may override the order
by simply calling the command multiple times and using the NO_*
options:
find_package (<PackageName> PATHS paths... NO_DEFAULT_PATH)
find_package (<PackageName>)
Once one of the calls succeeds the result variable will be set and
stored in the cache so that no call will search again.
By default the value stored in the result variable will be the path at
which the file is found. The CMAKE_FIND_PACKAGE_RESOLVE_SYMLINKS <#
variable:CMAKE_FIND_PACKAGE_RESOLVE_SYMLINKS> variable may be set to
TRUE before calling find_package in order to resolve symbolic links and
store the real path to the file.
Every non-REQUIRED find_package call can be disabled or made REQUIRED:
o Setting the CMAKE_DISABLE_FIND_PACKAGE_<PackageName> <#
variable:CMAKE_DISABLE_FIND_PACKAGE_<PackageName>> variable to TRUE
disables the package. This also disables redirection to a package
provided by FetchContent <#module:FetchContent>.
o Setting the CMAKE_REQUIRE_FIND_PACKAGE_<PackageName> <#
variable:CMAKE_REQUIRE_FIND_PACKAGE_<PackageName>> variable to TRUE
makes the package REQUIRED.
Setting both variables to TRUE simultaneously is an error.
Config Mode Version Selection
Note:
When Config mode is used, this version selection process is applied
regardless of whether the full or basic signature was given.
When the [version] argument is given, Config mode will only find a
version of the package that claims compatibility with the requested
version (see format specification). If the EXACT option is given, only
a version of the package claiming an exact match of the requested
version may be found. CMake does not establish any convention for the
meaning of version numbers. Package version numbers are checked by
"version" files provided by the packages themselves or by FetchContent
<#module:FetchContent>. For a candidate package configuration file
<config-file>.cmake the corresponding version file is located next to
it and named either <config-file>-version.cmake or
<config-file>Version.cmake. If no such version file is available then
the configuration file is assumed to not be compatible with any
requested version. A basic version file containing generic version
matching code can be created using the CMakePackageConfigHelpers <#
module:CMakePackageConfigHelpers> module. When a version file is found
it is loaded to check the requested version number. The version file
is loaded in a nested scope in which the following variables have been
defined:
PACKAGE_FIND_NAME
The <PackageName>
PACKAGE_FIND_VERSION
Full requested version string
PACKAGE_FIND_VERSION_MAJOR
Major version if requested, else 0
PACKAGE_FIND_VERSION_MINOR
Minor version if requested, else 0
PACKAGE_FIND_VERSION_PATCH
Patch version if requested, else 0
PACKAGE_FIND_VERSION_TWEAK
Tweak version if requested, else 0
PACKAGE_FIND_VERSION_COUNT
Number of version components, 0 to 4
When a version range is specified, the above version variables will
hold values based on the lower end of the version range. This is to
preserve compatibility with packages that have not been implemented to
expect version ranges. In addition, the version range will be
described by the following variables:
PACKAGE_FIND_VERSION_RANGE
Full requested version range string
PACKAGE_FIND_VERSION_RANGE_MIN
This specifies whether the lower end point of the version range
should be included or excluded. Currently, the only supported
value for this variable is INCLUDE.
PACKAGE_FIND_VERSION_RANGE_MAX
This specifies whether the upper end point of the version range
should be included or excluded. The supported values for this
variable are INCLUDE and EXCLUDE.
PACKAGE_FIND_VERSION_MIN
Full requested version string of the lower end point of the
range
PACKAGE_FIND_VERSION_MIN_MAJOR
Major version of the lower end point if requested, else 0
PACKAGE_FIND_VERSION_MIN_MINOR
Minor version of the lower end point if requested, else 0
PACKAGE_FIND_VERSION_MIN_PATCH
Patch version of the lower end point if requested, else 0
PACKAGE_FIND_VERSION_MIN_TWEAK
Tweak version of the lower end point if requested, else 0
PACKAGE_FIND_VERSION_MIN_COUNT
Number of version components of the lower end point, 0 to 4
PACKAGE_FIND_VERSION_MAX
Full requested version string of the upper end point of the
range
PACKAGE_FIND_VERSION_MAX_MAJOR
Major version of the upper end point if requested, else 0
PACKAGE_FIND_VERSION_MAX_MINOR
Minor version of the upper end point if requested, else 0
PACKAGE_FIND_VERSION_MAX_PATCH
Patch version of the upper end point if requested, else 0
PACKAGE_FIND_VERSION_MAX_TWEAK
Tweak version of the upper end point if requested, else 0
PACKAGE_FIND_VERSION_MAX_COUNT
Number of version components of the upper end point, 0 to 4
Regardless of whether a single version or a version range is specified,
the variable PACKAGE_FIND_VERSION_COMPLETE will be defined and will
hold the full requested version string as specified.
The version file checks whether it satisfies the requested version and
sets these variables:
PACKAGE_VERSION
Full provided version string
PACKAGE_VERSION_EXACT
True if version is exact match
PACKAGE_VERSION_COMPATIBLE
True if version is compatible
PACKAGE_VERSION_UNSUITABLE
True if unsuitable as any version
These variables are checked by the find_package command to determine
whether the configuration file provides an acceptable version. They
are not available after the find_package call returns. If the version
is acceptable the following variables are set:
<PackageName>_VERSION
Full provided version string
<PackageName>_VERSION_MAJOR
Major version if provided, else 0
<PackageName>_VERSION_MINOR
Minor version if provided, else 0
<PackageName>_VERSION_PATCH
Patch version if provided, else 0
<PackageName>_VERSION_TWEAK
Tweak version if provided, else 0
<PackageName>_VERSION_COUNT
Number of version components, 0 to 4
and the corresponding package configuration file is loaded.
Package File Interface Variables
When loading a find module or package configuration file find_package
defines variables to provide information about the call arguments (and
restores their original state before returning):
CMAKE_FIND_PACKAGE_NAME
The <PackageName> which is searched for
<PackageName>_FIND_REQUIRED
True if REQUIRED option was given
<PackageName>_FIND_QUIETLY
True if QUIET option was given
<PackageName>_FIND_REGISTRY_VIEW
The requested view if REGISTRY_VIEW option was given
<PackageName>_FIND_VERSION
Full requested version string
<PackageName>_FIND_VERSION_MAJOR
Major version if requested, else 0
<PackageName>_FIND_VERSION_MINOR
Minor version if requested, else 0
<PackageName>_FIND_VERSION_PATCH
Patch version if requested, else 0
<PackageName>_FIND_VERSION_TWEAK
Tweak version if requested, else 0
<PackageName>_FIND_VERSION_COUNT
Number of version components, 0 to 4
<PackageName>_FIND_VERSION_EXACT
True if EXACT option was given
<PackageName>_FIND_COMPONENTS
List of specified components (required and optional)
<PackageName>_FIND_REQUIRED_<c>
True if component <c> is required, false if component <c> is
optional
When a version range is specified, the above version variables will
hold values based on the lower end of the version range. This is to
preserve compatibility with packages that have not been implemented to
expect version ranges. In addition, the version range will be
described by the following variables:
<PackageName>_FIND_VERSION_RANGE
Full requested version range string
<PackageName>_FIND_VERSION_RANGE_MIN
This specifies whether the lower end point of the version range
is included or excluded. Currently, INCLUDE is the only
supported value.
<PackageName>_FIND_VERSION_RANGE_MAX
This specifies whether the upper end point of the version range
is included or excluded. The possible values for this variable
are INCLUDE or EXCLUDE.
<PackageName>_FIND_VERSION_MIN
Full requested version string of the lower end point of the
range
<PackageName>_FIND_VERSION_MIN_MAJOR
Major version of the lower end point if requested, else 0
<PackageName>_FIND_VERSION_MIN_MINOR
Minor version of the lower end point if requested, else 0
<PackageName>_FIND_VERSION_MIN_PATCH
Patch version of the lower end point if requested, else 0
<PackageName>_FIND_VERSION_MIN_TWEAK
Tweak version of the lower end point if requested, else 0
<PackageName>_FIND_VERSION_MIN_COUNT
Number of version components of the lower end point, 0 to 4
<PackageName>_FIND_VERSION_MAX
Full requested version string of the upper end point of the
range
<PackageName>_FIND_VERSION_MAX_MAJOR
Major version of the upper end point if requested, else 0
<PackageName>_FIND_VERSION_MAX_MINOR
Minor version of the upper end point if requested, else 0
<PackageName>_FIND_VERSION_MAX_PATCH
Patch version of the upper end point if requested, else 0
<PackageName>_FIND_VERSION_MAX_TWEAK
Tweak version of the upper end point if requested, else 0
<PackageName>_FIND_VERSION_MAX_COUNT
Number of version components of the upper end point, 0 to 4
Regardless of whether a single version or a version range is specified,
the variable <PackageName>_FIND_VERSION_COMPLETE will be defined and
will hold the full requested version string as specified.
In Module mode the loaded find module is responsible to honor the
request detailed by these variables; see the find module for details.
In Config mode find_package handles REQUIRED, QUIET, and [version]
options automatically but leaves it to the package configuration file
to handle components in a way that makes sense for the package. The
package configuration file may set <PackageName>_FOUND to false to tell
find_package that component requirements are not satisfied.
find_path
A short-hand signature is:
find_path (<VAR> name1 [path1 path2 ...])
The general signature is:
find_path (
<VAR>
name | NAMES name1 [name2 ...]
[HINTS [path | ENV var]... ]
[PATHS [path | ENV var]... ]
[REGISTRY_VIEW (64|32|64_32|32_64|HOST|TARGET|BOTH)]
[PATH_SUFFIXES suffix1 [suffix2 ...]]
[VALIDATOR function]
[DOC "cache documentation string"]
[NO_CACHE]
[REQUIRED]
[NO_DEFAULT_PATH]
[NO_PACKAGE_ROOT_PATH]
[NO_CMAKE_PATH]
[NO_CMAKE_ENVIRONMENT_PATH]
[NO_SYSTEM_ENVIRONMENT_PATH]
[NO_CMAKE_SYSTEM_PATH]
[NO_CMAKE_INSTALL_PREFIX]
[CMAKE_FIND_ROOT_PATH_BOTH |
ONLY_CMAKE_FIND_ROOT_PATH |
NO_CMAKE_FIND_ROOT_PATH]
)
This command is used to find a directory containing the named file. A
cache entry, or a normal variable if NO_CACHE is specified, named by
<VAR> is created to store the result of this command. If the file in a
directory is found the result is stored in the variable and the search
will not be repeated unless the variable is cleared. If nothing is
found, the result will be <VAR>-NOTFOUND.
Options include:
NAMES Specify one or more possible names for the file in a directory.
When using this to specify names with and without a version
suffix, we recommend specifying the unversioned name first so
that locally-built packages can be found before those provided
by distributions.
HINTS, PATHS
Specify directories to search in addition to the default
locations. The ENV var sub-option reads paths from a system
environment variable.
Changed in version 3.24: On Windows platform, it is possible to
include registry queries as part of the directories, using a
dedicated syntax <#find-using-windows-registry>. Such
specifications will be ignored on all other platforms.
REGISTRY_VIEW
Added in version 3.24.
Specify which registry views must be queried. This option is
only meaningful on Windows platforms and will be ignored on
other ones. When not specified, the TARGET view is used when the
CMP0134 <#policy:CMP0134> policy is NEW. Refer to CMP0134 <#
policy:CMP0134> for the default view when the policy is OLD.
64 Query the 64-bit registry. On 32-bit Windows, it always
returns the string /REGISTRY-NOTFOUND.
32 Query the 32-bit registry.
64_32 Query both views (64 and 32) and generate a path for
each.
32_64 Query both views (32 and 64) and generate a path for
each.
HOST Query the registry matching the architecture of the host:
64 on 64-bit Windows and 32 on 32-bit Windows.
TARGET Query the registry matching the architecture specified by
the CMAKE_SIZEOF_VOID_P <#variable:CMAKE_SIZEOF_VOID_P>
variable. If not defined, fall back to HOST view.
BOTH Query both views (32 and 64). The order depends on the
following rules: If the CMAKE_SIZEOF_VOID_P <#
variable:CMAKE_SIZEOF_VOID_P> variable is defined, use
the following view depending on the content of this
variable:
o 8: 64_32
o 4: 32_64
If the CMAKE_SIZEOF_VOID_P <#
variable:CMAKE_SIZEOF_VOID_P> variable is not defined,
rely on the architecture of the host:
o 64-bit: 64_32
o 32-bit: 32
PATH_SUFFIXES
Specify additional subdirectories to check below each directory
location otherwise considered.
VALIDATOR
Added in version 3.25.
Specify a function() <#command:function> to be called for each
candidate item found (a macro() <#command:macro> cannot be
provided, that will result in an error). Two arguments will be
passed to the validator function: the name of a result variable,
and the absolute path to the candidate item. The item will be
accepted and the search will end unless the function sets the
value in the result variable to false in the calling scope. The
result variable will hold a true value when the validator
function is entered.
function(my_check validator_result_var item)
if(NOT item MATCHES ...)
set(${validator_result_var} FALSE PARENT_SCOPE)
endif()
endfunction()
find_path (result NAMES ... VALIDATOR my_check)
Note that if a cached result is used, the search is skipped and
any VALIDATOR is ignored. The cached result is not required to
pass the validation function.
DOC Specify the documentation string for the <VAR> cache entry.
NO_CACHE
Added in version 3.21.
The result of the search will be stored in a normal variable
rather than a cache entry.
Note:
If the variable is already set before the call (as a normal
or cache variable) then the search will not occur.
Warning:
This option should be used with caution because it can
greatly increase the cost of repeated configure steps.
REQUIRED
Added in version 3.18.
Stop processing with an error message if nothing is found,
otherwise the search will be attempted again the next time
find_path is invoked with the same variable.
If NO_DEFAULT_PATH is specified, then no additional paths are added to
the search. If NO_DEFAULT_PATH is not specified, the search process is
as follows:
1. If called from within a find module or any other script loaded by a
call to find_package(<PackageName>) <#command:find_package>, search
prefixes unique to the current package being found. See policy
CMP0074 <#policy:CMP0074>.
Added in version 3.12.
Specifically, search paths specified by the following variables, in
order:
a. <PackageName>_ROOT <#variable:<PackageName>_ROOT> CMake variable,
where <PackageName> is the case-preserved package name.
b. <PACKAGENAME>_ROOT <#variable:<PACKAGENAME>_ROOT> CMake variable,
where <PACKAGENAME> is the upper-cased package name. See policy
CMP0144 <#policy:CMP0144>.
Added in version 3.27.
c. <PackageName>_ROOT <#envvar:<PackageName>_ROOT> environment
variable, where <PackageName> is the case-preserved package name.
d. <PACKAGENAME>_ROOT <#envvar:<PACKAGENAME>_ROOT> environment
variable, where <PACKAGENAME> is the upper-cased package name.
See policy CMP0144 <#policy:CMP0144>.
Added in version 3.27.
The package root variables are maintained as a stack, so if called
from nested find modules or config packages, root paths from the
parent's find module or config package will be searched after paths
from the current module or package. In other words, the search
order would be <CurrentPackage>_ROOT, ENV{<CurrentPackage>_ROOT},
<ParentPackage>_ROOT, ENV{<ParentPackage>_ROOT}, etc. This can be
skipped if NO_PACKAGE_ROOT_PATH is passed or by setting the
CMAKE_FIND_USE_PACKAGE_ROOT_PATH <#
variable:CMAKE_FIND_USE_PACKAGE_ROOT_PATH> to FALSE.
o <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/include
for each <prefix> in the <PackageName>_ROOT <#
variable:<PackageName>_ROOT> CMake variable and the
<PackageName>_ROOT <#envvar:<PackageName>_ROOT> environment
variable if called from within a find module loaded by
find_package(<PackageName>) <#command:find_package>
2. Search paths specified in cmake-specific cache variables. These are
intended to be used on the command line with a -DVAR=value. The
values are interpreted as semicolon-separated lists <#cmake-
language-lists>. This can be skipped if NO_CMAKE_PATH is passed or
by setting the CMAKE_FIND_USE_CMAKE_PATH <#
variable:CMAKE_FIND_USE_CMAKE_PATH> to FALSE.
o <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/include
for each <prefix> in CMAKE_PREFIX_PATH <#
variable:CMAKE_PREFIX_PATH>
o CMAKE_INCLUDE_PATH <#variable:CMAKE_INCLUDE_PATH>
o CMAKE_FRAMEWORK_PATH <#variable:CMAKE_FRAMEWORK_PATH>
3. Search paths specified in cmake-specific environment variables.
These are intended to be set in the user's shell configuration, and
therefore use the host's native path separator (; on Windows and :
on UNIX). This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is
passed or by setting the CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH <#
variable:CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH> to FALSE.
o <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/include
for each <prefix> in CMAKE_PREFIX_PATH <#envvar:CMAKE_PREFIX_PATH>
o CMAKE_INCLUDE_PATH <#envvar:CMAKE_INCLUDE_PATH>
o CMAKE_FRAMEWORK_PATH <#envvar:CMAKE_FRAMEWORK_PATH>
4. Search the paths specified by the HINTS option. These should be
paths computed by system introspection, such as a hint provided by
the location of another item already found. Hard-coded guesses
should be specified with the PATHS option.
5. Search the standard system environment variables. This can be
skipped if NO_SYSTEM_ENVIRONMENT_PATH is passed or by setting the
CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH <#
variable:CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH> to FALSE.
o The directories in INCLUDE and PATH.
On Windows hosts, CMake 3.3 through 3.27 searched additional paths:
<prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/include
for each <prefix>/[s]bin in PATH, and <entry>/include for other
entries in PATH. This behavior was removed by CMake 3.28.
6. Search cmake variables defined in the Platform files for the current
system. The searching of CMAKE_INSTALL_PREFIX and
CMAKE_STAGING_PREFIX can be skipped if NO_CMAKE_INSTALL_PREFIX is
passed or by setting the CMAKE_FIND_USE_INSTALL_PREFIX <#
variable:CMAKE_FIND_USE_INSTALL_PREFIX> to FALSE. All these
locations can be skipped if NO_CMAKE_SYSTEM_PATH is passed or by
setting the CMAKE_FIND_USE_CMAKE_SYSTEM_PATH <#
variable:CMAKE_FIND_USE_CMAKE_SYSTEM_PATH> to FALSE.
o <prefix>/include/<arch> if CMAKE_LIBRARY_ARCHITECTURE <#
variable:CMAKE_LIBRARY_ARCHITECTURE> is set, and <prefix>/include
for each <prefix> in CMAKE_SYSTEM_PREFIX_PATH <#
variable:CMAKE_SYSTEM_PREFIX_PATH>
o CMAKE_SYSTEM_INCLUDE_PATH <#variable:CMAKE_SYSTEM_INCLUDE_PATH>
o CMAKE_SYSTEM_FRAMEWORK_PATH <#
variable:CMAKE_SYSTEM_FRAMEWORK_PATH>
The platform paths that these variables contain are locations that
typically include installed software. An example being /usr/local
for UNIX based platforms.
7. Search the paths specified by the PATHS option or in the short-hand
version of the command. These are typically hard-coded guesses.
The CMAKE_IGNORE_PATH <#variable:CMAKE_IGNORE_PATH>,
CMAKE_IGNORE_PREFIX_PATH <#variable:CMAKE_IGNORE_PREFIX_PATH>,
CMAKE_SYSTEM_IGNORE_PATH <#variable:CMAKE_SYSTEM_IGNORE_PATH> and
CMAKE_SYSTEM_IGNORE_PREFIX_PATH <#
variable:CMAKE_SYSTEM_IGNORE_PREFIX_PATH> variables can also cause some
of the above locations to be ignored.
Added in version 3.16: Added CMAKE_FIND_USE_<CATEGORY>_PATH variables
to globally disable various search locations.
On macOS the CMAKE_FIND_FRAMEWORK <#variable:CMAKE_FIND_FRAMEWORK> and
CMAKE_FIND_APPBUNDLE <#variable:CMAKE_FIND_APPBUNDLE> variables
determine the order of preference between Apple-style and unix-style
package components.
The CMake variable CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> specifies one or more directories to be
prepended to all other search directories. This effectively "re-roots"
the entire search under given locations. Paths which are descendants
of the CMAKE_STAGING_PREFIX <#variable:CMAKE_STAGING_PREFIX> are
excluded from this re-rooting, because that variable is always a path
on the host system. By default the CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> is empty.
The CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> variable can also be used
to specify exactly one directory to use as a prefix. Setting
CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> also has other effects. See
the documentation for that variable for more.
These variables are especially useful when cross-compiling to point to
the root directory of the target environment and CMake will search
there too. By default at first the directories listed in
CMAKE_FIND_ROOT_PATH <#variable:CMAKE_FIND_ROOT_PATH> are searched,
then the CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> directory is searched,
and then the non-rooted directories will be searched. The default
behavior can be adjusted by setting CMAKE_FIND_ROOT_PATH_MODE_INCLUDE
<#variable:CMAKE_FIND_ROOT_PATH_MODE_INCLUDE>. This behavior can be
manually overridden on a per-call basis using options:
CMAKE_FIND_ROOT_PATH_BOTH
Search in the order described above.
NO_CMAKE_FIND_ROOT_PATH
Do not use the CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> variable.
ONLY_CMAKE_FIND_ROOT_PATH
Search only the re-rooted directories and directories below
CMAKE_STAGING_PREFIX <#variable:CMAKE_STAGING_PREFIX>.
The default search order is designed to be most-specific to
least-specific for common use cases. Projects may override the order
by simply calling the command multiple times and using the NO_*
options:
find_path (<VAR> NAMES name PATHS paths... NO_DEFAULT_PATH)
find_path (<VAR> NAMES name)
Once one of the calls succeeds the result variable will be set and
stored in the cache so that no call will search again.
When searching for frameworks, if the file is specified as A/b.h, then
the framework search will look for A.framework/Headers/b.h. If that is
found the path will be set to the path to the framework. CMake will
convert this to the correct -F option to include the file.
find_program
A short-hand signature is:
find_program (<VAR> name1 [path1 path2 ...])
The general signature is:
find_program (
<VAR>
name | NAMES name1 [name2 ...] [NAMES_PER_DIR]
[HINTS [path | ENV var]... ]
[PATHS [path | ENV var]... ]
[REGISTRY_VIEW (64|32|64_32|32_64|HOST|TARGET|BOTH)]
[PATH_SUFFIXES suffix1 [suffix2 ...]]
[VALIDATOR function]
[DOC "cache documentation string"]
[NO_CACHE]
[REQUIRED]
[NO_DEFAULT_PATH]
[NO_PACKAGE_ROOT_PATH]
[NO_CMAKE_PATH]
[NO_CMAKE_ENVIRONMENT_PATH]
[NO_SYSTEM_ENVIRONMENT_PATH]
[NO_CMAKE_SYSTEM_PATH]
[NO_CMAKE_INSTALL_PREFIX]
[CMAKE_FIND_ROOT_PATH_BOTH |
ONLY_CMAKE_FIND_ROOT_PATH |
NO_CMAKE_FIND_ROOT_PATH]
)
This command is used to find a program. A cache entry, or a normal
variable if NO_CACHE is specified, named by <VAR> is created to store
the result of this command. If the program is found the result is
stored in the variable and the search will not be repeated unless the
variable is cleared. If nothing is found, the result will be
<VAR>-NOTFOUND.
Options include:
NAMES Specify one or more possible names for the program.
When using this to specify names with and without a version
suffix, we recommend specifying the unversioned name first so
that locally-built packages can be found before those provided
by distributions.
HINTS, PATHS
Specify directories to search in addition to the default
locations. The ENV var sub-option reads paths from a system
environment variable.
Changed in version 3.24: On Windows platform, it is possible to
include registry queries as part of the directories, using a
dedicated syntax <#find-using-windows-registry>. Such
specifications will be ignored on all other platforms.
REGISTRY_VIEW
Added in version 3.24.
Specify which registry views must be queried. This option is
only meaningful on Windows platforms and will be ignored on
other ones. When not specified, the BOTH view is used when the
CMP0134 <#policy:CMP0134> policy is NEW. Refer to CMP0134 <#
policy:CMP0134> for the default view when the policy is OLD.
64 Query the 64-bit registry. On 32-bit Windows, it always
returns the string /REGISTRY-NOTFOUND.
32 Query the 32-bit registry.
64_32 Query both views (64 and 32) and generate a path for
each.
32_64 Query both views (32 and 64) and generate a path for
each.
HOST Query the registry matching the architecture of the host:
64 on 64-bit Windows and 32 on 32-bit Windows.
TARGET Query the registry matching the architecture specified by
the CMAKE_SIZEOF_VOID_P <#variable:CMAKE_SIZEOF_VOID_P>
variable. If not defined, fall back to HOST view.
BOTH Query both views (32 and 64). The order depends on the
following rules: If the CMAKE_SIZEOF_VOID_P <#
variable:CMAKE_SIZEOF_VOID_P> variable is defined, use
the following view depending on the content of this
variable:
o 8: 64_32
o 4: 32_64
If the CMAKE_SIZEOF_VOID_P <#
variable:CMAKE_SIZEOF_VOID_P> variable is not defined,
rely on the architecture of the host:
o 64-bit: 64_32
o 32-bit: 32
PATH_SUFFIXES
Specify additional subdirectories to check below each directory
location otherwise considered.
VALIDATOR
Added in version 3.25.
Specify a function() <#command:function> to be called for each
candidate item found (a macro() <#command:macro> cannot be
provided, that will result in an error). Two arguments will be
passed to the validator function: the name of a result variable,
and the absolute path to the candidate item. The item will be
accepted and the search will end unless the function sets the
value in the result variable to false in the calling scope. The
result variable will hold a true value when the validator
function is entered.
function(my_check validator_result_var item)
if(NOT item MATCHES ...)
set(${validator_result_var} FALSE PARENT_SCOPE)
endif()
endfunction()
find_program (result NAMES ... VALIDATOR my_check)
Note that if a cached result is used, the search is skipped and
any VALIDATOR is ignored. The cached result is not required to
pass the validation function.
DOC Specify the documentation string for the <VAR> cache entry.
NO_CACHE
Added in version 3.21.
The result of the search will be stored in a normal variable
rather than a cache entry.
Note:
If the variable is already set before the call (as a normal
or cache variable) then the search will not occur.
Warning:
This option should be used with caution because it can
greatly increase the cost of repeated configure steps.
REQUIRED
Added in version 3.18.
Stop processing with an error message if nothing is found,
otherwise the search will be attempted again the next time
find_program is invoked with the same variable.
If NO_DEFAULT_PATH is specified, then no additional paths are added to
the search. If NO_DEFAULT_PATH is not specified, the search process is
as follows:
1. If called from within a find module or any other script loaded by a
call to find_package(<PackageName>) <#command:find_package>, search
prefixes unique to the current package being found. See policy
CMP0074 <#policy:CMP0074>.
Added in version 3.12.
Specifically, search paths specified by the following variables, in
order:
a. <PackageName>_ROOT <#variable:<PackageName>_ROOT> CMake variable,
where <PackageName> is the case-preserved package name.
b. <PACKAGENAME>_ROOT <#variable:<PACKAGENAME>_ROOT> CMake variable,
where <PACKAGENAME> is the upper-cased package name. See policy
CMP0144 <#policy:CMP0144>.
Added in version 3.27.
c. <PackageName>_ROOT <#envvar:<PackageName>_ROOT> environment
variable, where <PackageName> is the case-preserved package name.
d. <PACKAGENAME>_ROOT <#envvar:<PACKAGENAME>_ROOT> environment
variable, where <PACKAGENAME> is the upper-cased package name.
See policy CMP0144 <#policy:CMP0144>.
Added in version 3.27.
The package root variables are maintained as a stack, so if called
from nested find modules or config packages, root paths from the
parent's find module or config package will be searched after paths
from the current module or package. In other words, the search
order would be <CurrentPackage>_ROOT, ENV{<CurrentPackage>_ROOT},
<ParentPackage>_ROOT, ENV{<ParentPackage>_ROOT}, etc. This can be
skipped if NO_PACKAGE_ROOT_PATH is passed or by setting the
CMAKE_FIND_USE_PACKAGE_ROOT_PATH <#
variable:CMAKE_FIND_USE_PACKAGE_ROOT_PATH> to FALSE.
o <prefix>/[s]bin for each <prefix> in the <PackageName>_ROOT <#
variable:<PackageName>_ROOT> CMake variable and the
<PackageName>_ROOT <#envvar:<PackageName>_ROOT> environment
variable if called from within a find module loaded by
find_package(<PackageName>) <#command:find_package>
2. Search paths specified in cmake-specific cache variables. These are
intended to be used on the command line with a -DVAR=value. The
values are interpreted as semicolon-separated lists <#cmake-
language-lists>. This can be skipped if NO_CMAKE_PATH is passed or
by setting the CMAKE_FIND_USE_CMAKE_PATH <#
variable:CMAKE_FIND_USE_CMAKE_PATH> to FALSE.
o <prefix>/[s]bin for each <prefix> in CMAKE_PREFIX_PATH <#
variable:CMAKE_PREFIX_PATH>
o CMAKE_PROGRAM_PATH <#variable:CMAKE_PROGRAM_PATH>
o CMAKE_APPBUNDLE_PATH <#variable:CMAKE_APPBUNDLE_PATH>
3. Search paths specified in cmake-specific environment variables.
These are intended to be set in the user's shell configuration, and
therefore use the host's native path separator (; on Windows and :
on UNIX). This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is
passed or by setting the CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH <#
variable:CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH> to FALSE.
o <prefix>/[s]bin for each <prefix> in CMAKE_PREFIX_PATH <#
envvar:CMAKE_PREFIX_PATH>
o CMAKE_PROGRAM_PATH <#envvar:CMAKE_PROGRAM_PATH>
o CMAKE_APPBUNDLE_PATH <#envvar:CMAKE_APPBUNDLE_PATH>
4. Search the paths specified by the HINTS option. These should be
paths computed by system introspection, such as a hint provided by
the location of another item already found. Hard-coded guesses
should be specified with the PATHS option.
5. Search the standard system environment variables. This can be
skipped if NO_SYSTEM_ENVIRONMENT_PATH is passed or by setting the
CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH <#
variable:CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH> to FALSE.
o The directories in PATH itself.
6. Search cmake variables defined in the Platform files for the current
system. The searching of CMAKE_INSTALL_PREFIX and
CMAKE_STAGING_PREFIX can be skipped if NO_CMAKE_INSTALL_PREFIX is
passed or by setting the CMAKE_FIND_USE_INSTALL_PREFIX <#
variable:CMAKE_FIND_USE_INSTALL_PREFIX> to FALSE. All these
locations can be skipped if NO_CMAKE_SYSTEM_PATH is passed or by
setting the CMAKE_FIND_USE_CMAKE_SYSTEM_PATH <#
variable:CMAKE_FIND_USE_CMAKE_SYSTEM_PATH> to FALSE.
o <prefix>/[s]bin for each <prefix> in CMAKE_SYSTEM_PREFIX_PATH <#
variable:CMAKE_SYSTEM_PREFIX_PATH>
o CMAKE_SYSTEM_PROGRAM_PATH <#variable:CMAKE_SYSTEM_PROGRAM_PATH>
o CMAKE_SYSTEM_APPBUNDLE_PATH <#
variable:CMAKE_SYSTEM_APPBUNDLE_PATH>
The platform paths that these variables contain are locations that
typically include installed software. An example being /usr/local
for UNIX based platforms.
7. Search the paths specified by the PATHS option or in the short-hand
version of the command. These are typically hard-coded guesses.
The CMAKE_IGNORE_PATH <#variable:CMAKE_IGNORE_PATH>,
CMAKE_IGNORE_PREFIX_PATH <#variable:CMAKE_IGNORE_PREFIX_PATH>,
CMAKE_SYSTEM_IGNORE_PATH <#variable:CMAKE_SYSTEM_IGNORE_PATH> and
CMAKE_SYSTEM_IGNORE_PREFIX_PATH <#
variable:CMAKE_SYSTEM_IGNORE_PREFIX_PATH> variables can also cause some
of the above locations to be ignored.
Added in version 3.16: Added CMAKE_FIND_USE_<CATEGORY>_PATH variables
to globally disable various search locations.
On macOS the CMAKE_FIND_FRAMEWORK <#variable:CMAKE_FIND_FRAMEWORK> and
CMAKE_FIND_APPBUNDLE <#variable:CMAKE_FIND_APPBUNDLE> variables
determine the order of preference between Apple-style and unix-style
package components.
The CMake variable CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> specifies one or more directories to be
prepended to all other search directories. This effectively "re-roots"
the entire search under given locations. Paths which are descendants
of the CMAKE_STAGING_PREFIX <#variable:CMAKE_STAGING_PREFIX> are
excluded from this re-rooting, because that variable is always a path
on the host system. By default the CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> is empty.
The CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> variable can also be used
to specify exactly one directory to use as a prefix. Setting
CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> also has other effects. See
the documentation for that variable for more.
These variables are especially useful when cross-compiling to point to
the root directory of the target environment and CMake will search
there too. By default at first the directories listed in
CMAKE_FIND_ROOT_PATH <#variable:CMAKE_FIND_ROOT_PATH> are searched,
then the CMAKE_SYSROOT <#variable:CMAKE_SYSROOT> directory is searched,
and then the non-rooted directories will be searched. The default
behavior can be adjusted by setting CMAKE_FIND_ROOT_PATH_MODE_PROGRAM
<#variable:CMAKE_FIND_ROOT_PATH_MODE_PROGRAM>. This behavior can be
manually overridden on a per-call basis using options:
CMAKE_FIND_ROOT_PATH_BOTH
Search in the order described above.
NO_CMAKE_FIND_ROOT_PATH
Do not use the CMAKE_FIND_ROOT_PATH <#
variable:CMAKE_FIND_ROOT_PATH> variable.
ONLY_CMAKE_FIND_ROOT_PATH
Search only the re-rooted directories and directories below
CMAKE_STAGING_PREFIX <#variable:CMAKE_STAGING_PREFIX>.
The default search order is designed to be most-specific to
least-specific for common use cases. Projects may override the order
by simply calling the command multiple times and using the NO_*
options:
find_program (<VAR> NAMES name PATHS paths... NO_DEFAULT_PATH)
find_program (<VAR> NAMES name)
Once one of the calls succeeds the result variable will be set and
stored in the cache so that no call will search again.
When more than one value is given to the NAMES option this command by
default will consider one name at a time and search every directory for
it. The NAMES_PER_DIR option tells this command to consider one
directory at a time and search for all names in it.
The set of files considered to be programs is platform-specific:
o On Windows, filename suffixes are considered in order .com, .exe, and
no suffix.
o On non-Windows systems, no filename suffix is considered, but files
must have execute permission (see policy CMP0109 <#policy:CMP0109>).
To search for scripts, specify an extension explicitly:
if(WIN32)
set(_script_suffix .bat)
else()
set(_script_suffix .sh)
endif()
find_program(MY_SCRIPT NAMES my_script${_script_suffix})
foreach
Evaluate a group of commands for each value in a list.
foreach(<loop_var> <items>)
<commands>
endforeach()
where <items> is a list of items that are separated by semicolon or
whitespace. All commands between foreach and the matching endforeach
are recorded without being invoked. Once the endforeach is evaluated,
the recorded list of commands is invoked once for each item in <items>.
At the beginning of each iteration the variable <loop_var> will be set
to the value of the current item.
The scope of <loop_var> is restricted to the loop scope. See policy
CMP0124 <#policy:CMP0124> for details.
The commands break() <#command:break> and continue() <#
command:continue> provide means to escape from the normal control flow.
Per legacy, the endforeach() <#command:endforeach> command admits an
optional <loop_var> argument. If used, it must be a verbatim repeat of
the argument of the opening foreach command.
foreach(<loop_var> RANGE <stop>)
In this variant, foreach iterates over the numbers 0, 1, ... up to (and
including) the nonnegative integer <stop>.
foreach(<loop_var> RANGE <start> <stop> [<step>])
In this variant, foreach iterates over the numbers from <start> up to
at most <stop> in steps of <step>. If <step> is not specified, then
the step size is 1. The three arguments <start> <stop> <step> must all
be nonnegative integers, and <stop> must not be smaller than <start>;
otherwise you enter the danger zone of undocumented behavior that may
change in future releases.
foreach(<loop_var> IN [LISTS [<lists>]] [ITEMS [<items>]])
In this variant, <lists> is a whitespace or semicolon separated list of
list-valued variables. The foreach command iterates over each item in
each given list. The <items> following the ITEMS keyword are processed
as in the first variant of the foreach command. The forms LISTS A and
ITEMS ${A} are equivalent.
The following example shows how the LISTS option is processed:
set(A 0;1)
set(B 2 3)
set(C "4 5")
set(D 6;7 8)
set(E "")
foreach(X IN LISTS A B C D E)
message(STATUS "X=${X}")
endforeach()
yields:
-- X=0
-- X=1
-- X=2
-- X=3
-- X=4 5
-- X=6
-- X=7
-- X=8
foreach(<loop_var>... IN ZIP_LISTS <lists>)
Added in version 3.17.
In this variant, <lists> is a whitespace or semicolon separated list of
list-valued variables. The foreach command iterates over each list
simultaneously setting the iteration variables as follows:
o if the only loop_var given, then it sets a series of loop_var_N
variables to the current item from the corresponding list;
o if multiple variable names passed, their count should match the lists
variables count;
o if any of the lists are shorter, the corresponding iteration variable
is not defined for the current iteration.
list(APPEND English one two three four)
list(APPEND Bahasa satu dua tiga)
foreach(num IN ZIP_LISTS English Bahasa)
message(STATUS "num_0=${num_0}, num_1=${num_1}")
endforeach()
foreach(en ba IN ZIP_LISTS English Bahasa)
message(STATUS "en=${en}, ba=${ba}")
endforeach()
yields:
-- num_0=one, num_1=satu
-- num_0=two, num_1=dua
-- num_0=three, num_1=tiga
-- num_0=four, num_1=
-- en=one, ba=satu
-- en=two, ba=dua
-- en=three, ba=tiga
-- en=four, ba=
See Also
o break() <#command:break>
o continue() <#command:continue>
o endforeach() <#command:endforeach>
o while() <#command:while>
function
Start recording a function for later invocation as a command.
function(<name> [<arg1> ...])
<commands>
endfunction()
Defines a function named <name> that takes arguments named <arg1>, ...
The <commands> in the function definition are recorded; they are not
executed until the function is invoked.
Per legacy, the endfunction() <#command:endfunction> command admits an
optional <name> argument. If used, it must be a verbatim repeat of the
argument of the opening function command.
A function opens a new scope: see set(var PARENT_SCOPE) <#command:set>
for details.
See the cmake_policy() <#command:cmake_policy> command documentation
for the behavior of policies inside functions.
See the macro() <#command:macro> command documentation for differences
between CMake functions and macros.
Invocation
The function invocation is case-insensitive. A function defined as
function(foo)
<commands>
endfunction()
can be invoked through any of
foo()
Foo()
FOO()
cmake_language(CALL foo)
and so on. However, it is strongly recommended to stay with the case
chosen in the function definition. Typically functions use
all-lowercase names.
Added in version 3.18: The cmake_language(CALL ...) <#
command:cmake_language> command can also be used to invoke the
function.
Arguments
When the function is invoked, the recorded <commands> are first
modified by replacing formal parameters (${arg1}, ...) with the
arguments passed, and then invoked as normal commands.
In addition to referencing the formal parameters you can reference the
ARGC variable which will be set to the number of arguments passed into
the function as well as ARGV0, ARGV1, ARGV2, ... which will have the
actual values of the arguments passed in. This facilitates creating
functions with optional arguments.
Furthermore, ARGV holds the list of all arguments given to the function
and ARGN holds the list of arguments past the last expected argument.
Referencing to ARGV# arguments beyond ARGC have undefined behavior.
Checking that ARGC is greater than # is the only way to ensure that
ARGV# was passed to the function as an extra argument.
See Also
o cmake_parse_arguments() <#command:cmake_parse_arguments>
o endfunction() <#command:endfunction>
o return() <#command:return>
get_cmake_property
Get a global property of the CMake instance.
get_cmake_property(<variable> <property>)
Gets a global property from the CMake instance. The value of the
<property> is stored in the specified <variable>. If the property is
not found, <variable> will be set to NOTFOUND. See the
cmake-properties(7) <#manual:cmake-properties(7)> manual for available
properties.
In addition to global properties, this command (for historical reasons)
also supports the VARIABLES <#prop_dir:VARIABLES> and MACROS <#
prop_dir:MACROS> directory properties. It also supports a special
COMPONENTS global property that lists the components given to the
install() <#command:install> command.
See Also
o the get_property() <#command:get_property> command GLOBAL option
get_directory_property
Get a property of DIRECTORY scope.
get_directory_property(<variable> [DIRECTORY <dir>] <prop-name>)
Stores a property of directory scope in the named <variable>.
The DIRECTORY argument specifies another directory from which to
retrieve the property value instead of the current directory. Relative
paths are treated as relative to the current source directory. CMake
must already know about the directory, either by having added it
through a call to add_subdirectory() <#command:add_subdirectory> or
being the top level directory.
Added in version 3.19: <dir> may reference a binary directory.
If the property is not defined for the nominated directory scope, an
empty string is returned. In the case of INHERITED properties, if the
property is not found for the nominated directory scope, the search
will chain to a parent scope as described for the define_property() <#
command:define_property> command.
get_directory_property(<variable> [DIRECTORY <dir>]
DEFINITION <var-name>)
Get a variable definition from a directory. This form is useful to get
a variable definition from another directory.
See Also
o define_property() <#command:define_property>
o the more general get_property() <#command:get_property> command
get_filename_component
Get a specific component of a full filename.
Changed in version 3.20: This command has been superseded by the
cmake_path() <#command:cmake_path> command, except for REALPATH, which
is now offered by file(REAL_PATH) <#real-path>, and PROGRAM, now
available in separate_arguments(PROGRAM) <#command:separate_arguments>.
Changed in version 3.24: The undocumented feature offering the
capability to query the Windows registry is superseded by
cmake_host_system_information(QUERY WINDOWS_REGISTRY) <#query-windows-
registry> command.
get_filename_component(<var> <FileName> <mode> [CACHE])
Sets <var> to a component of <FileName>, where <mode> is one of:
DIRECTORY = Directory without file name
NAME = File name without directory
EXT = File name longest extension (.b.c from d/a.b.c)
NAME_WE = File name with neither the directory nor the longest extension
LAST_EXT = File name last extension (.c from d/a.b.c)
NAME_WLE = File name with neither the directory nor the last extension
PATH = Legacy alias for DIRECTORY (use for CMake <= 2.8.11)
Added in version 3.14: Added the LAST_EXT and NAME_WLE modes.
Paths are returned with forward slashes and have no trailing slashes.
If the optional CACHE argument is specified, the result variable is
added to the cache.
get_filename_component(<var> <FileName> <mode> [BASE_DIR <dir>] [CACHE])
Added in version 3.4.
Sets <var> to the absolute path of <FileName>, where <mode> is one of:
ABSOLUTE = Full path to file
REALPATH = Full path to existing file with symlinks resolved
If the provided <FileName> is a relative path, it is evaluated relative
to the given base directory <dir>. If no base directory is provided,
the default base directory will be CMAKE_CURRENT_SOURCE_DIR <#
variable:CMAKE_CURRENT_SOURCE_DIR>.
Paths are returned with forward slashes and have no trailing slashes.
If the optional CACHE argument is specified, the result variable is
added to the cache.
get_filename_component(<var> <FileName> PROGRAM [PROGRAM_ARGS <arg_var>] [CACHE])
The program in <FileName> will be found in the system search path or
left as a full path. If PROGRAM_ARGS is present with PROGRAM, then any
command-line arguments present in the <FileName> string are split from
the program name and stored in <arg_var>. This is used to separate a
program name from its arguments in a command line string.
See Also
o cmake_path() <#command:cmake_path>
get_property
Get a property.
get_property(<variable>
<GLOBAL |
DIRECTORY [<dir>] |
TARGET <target> |
SOURCE <source>
[DIRECTORY <dir> | TARGET_DIRECTORY <target>] |
INSTALL <file> |
TEST <test>
[DIRECTORY <dir>] |
CACHE <entry> |
VARIABLE >
PROPERTY <name>
[SET | DEFINED | BRIEF_DOCS | FULL_DOCS])
Gets one property from one object in a scope.
The first argument specifies the variable in which to store the result.
The second argument determines the scope from which to get the
property. It must be one of the following:
GLOBAL Scope is unique and does not accept a name.
DIRECTORY
Scope defaults to the current directory, but another directory
(already processed by CMake) may be named by the full or
relative path <dir>. Relative paths are treated as relative to
the current source directory. See also the
get_directory_property() <#command:get_directory_property>
command.
Added in version 3.19: <dir> may reference a binary directory.
TARGET Scope must name one existing target. See also the
get_target_property() <#command:get_target_property> command.
SOURCE Scope must name one source file. By default, the source file's
property will be read from the current source directory's scope.
Added in version 3.18: Directory scope can be overridden with
one of the following sub-options:
DIRECTORY <dir>
The source file property will be read from the <dir>
directory's scope. CMake must already know about the
directory, either by having added it through a call to
add_subdirectory() <#command:add_subdirectory> or <dir>
being the top level directory. Relative paths are
treated as relative to the current source directory.
Added in version 3.19: <dir> may reference a binary
directory.
TARGET_DIRECTORY <target>
The source file property will be read from the directory
scope in which <target> was created (<target> must
therefore already exist).
See also the get_source_file_property() <#
command:get_source_file_property> command.
INSTALL
Added in version 3.1.
Scope must name one installed file path.
TEST Scope must name one existing test. See also the
get_test_property() <#command:get_test_property> command.
Added in version 3.28: Directory scope can be overridden with
the following sub-option:
DIRECTORY <dir>
The test property will be read from the <dir> directory's
scope. CMake must already know about the directory,
either by having added it through a call to
add_subdirectory() <#command:add_subdirectory> or <dir>
being the top level directory. Relative paths are treated
as relative to the current source directory. <dir> may
reference a binary directory.
CACHE Scope must name one cache entry.
VARIABLE
Scope is unique and does not accept a name.
The required PROPERTY option is immediately followed by the name of the
property to get. If the property is not set, the named <variable> will
be unset in the calling scope upon return, although some properties
support inheriting from a parent scope if defined to behave that way
(see define_property() <#command:define_property>).
If the SET option is given, the variable is set to a boolean value
indicating whether the property has been set. If the DEFINED option is
given, the variable is set to a boolean value indicating whether the
property has been defined, such as with the define_property() <#
command:define_property> command.
If BRIEF_DOCS or FULL_DOCS is given, then the variable is set to a
string containing documentation for the requested property. If
documentation is requested for a property that has not been defined,
NOTFOUND is returned.
Note:
The GENERATED <#prop_sf:GENERATED> source file property may be
globally visible. See its documentation for details.
See Also
o define_property() <#command:define_property>
o set_property() <#command:set_property>
if
Conditionally execute a group of commands.
Synopsis
if(<condition>)
<commands>
elseif(<condition>) # optional block, can be repeated
<commands>
else() # optional block
<commands>
endif()
Evaluates the condition argument of the if clause according to the
Condition syntax described below. If the result is true, then the
commands in the if block are executed. Otherwise, optional elseif
blocks are processed in the same way. Finally, if no condition is
true, commands in the optional else block are executed.
Per legacy, the else() <#command:else> and endif() <#command:endif>
commands admit an optional <condition> argument. If used, it must be a
verbatim repeat of the argument of the opening if command.
Condition Syntax
The following syntax applies to the condition argument of the if,
elseif and while() <#command:while> clauses.
Compound conditions are evaluated in the following order of precedence:
1. Parentheses.
2. Unary tests such as COMMAND, POLICY, TARGET, TEST, EXISTS,
IS_READABLE, IS_WRITABLE, IS_EXECUTABLE, IS_DIRECTORY, IS_SYMLINK,
IS_ABSOLUTE, and DEFINED.
3. Binary tests such as EQUAL, LESS, LESS_EQUAL, GREATER,
GREATER_EQUAL, STREQUAL, STRLESS, STRLESS_EQUAL, STRGREATER,
STRGREATER_EQUAL, VERSION_EQUAL, VERSION_LESS, VERSION_LESS_EQUAL,
VERSION_GREATER, VERSION_GREATER_EQUAL, PATH_EQUAL, IN_LIST,
IS_NEWER_THAN, and MATCHES.
4. Unary logical operator NOT.
5. Binary logical operators AND and OR, from left to right, without any
short-circuit.
Basic Expressions
if(<constant>)
True if the constant is 1, ON, YES, TRUE, Y, or a non-zero
number (including floating point numbers). False if the
constant is 0, OFF, NO, FALSE, N, IGNORE, NOTFOUND, the empty
string, or ends in the suffix -NOTFOUND. Named boolean
constants are case-insensitive. If the argument is not one of
these specific constants, it is treated as a variable or string
(see Variable Expansion further below) and one of the following
two forms applies.
if(<variable>)
True if given a variable that is defined to a value that is not
a false constant. False otherwise, including if the variable is
undefined. Note that macro arguments are not variables.
Environment Variables <#cmake-language-environment-variables>
also cannot be tested this way, e.g. if(ENV{some_var}) will
always evaluate to false.
if(<string>)
A quoted string always evaluates to false unless:
o The string's value is one of the true constants, or
o Policy CMP0054 <#policy:CMP0054> is not set to NEW and the
string's value happens to be a variable name that is affected
by CMP0054 <#policy:CMP0054>'s behavior.
Logic Operators
if(NOT <condition>)
True if the condition is not true.
if(<cond1> AND <cond2>)
True if both conditions would be considered true individually.
if(<cond1> OR <cond2>)
True if either condition would be considered true individually.
if((condition) AND (condition OR (condition)))
The conditions inside the parenthesis are evaluated first and
then the remaining condition is evaluated as in the other
examples. Where there are nested parenthesis the innermost are
evaluated as part of evaluating the condition that contains
them.
Existence Checks
if(COMMAND <command-name>)
True if the given name is a command, macro or function that can
be invoked.
if(POLICY <policy-id>)
True if the given name is an existing policy (of the form
CMP<NNNN>).
if(TARGET <target-name>)
True if the given name is an existing logical target name
created by a call to the add_executable() <#
command:add_executable>, add_library() <#command:add_library>,
or add_custom_target() <#command:add_custom_target> command that
has already been invoked (in any directory).
if(TEST <test-name>)
Added in version 3.3.
True if the given name is an existing test name created by the
add_test() <#command:add_test> command.
if(DEFINED <name>|CACHE{<name>}|ENV{<name>})
True if a variable, cache variable or environment variable
with given <name> is defined. The value of the variable does
not matter. Note the following caveats:
o Macro arguments are not variables.
o It is not possible to test directly whether a <name> is a
non-cache variable. The expression if(DEFINED someName)
will evaluate to true if either a cache or non-cache
variable someName exists. In comparison, the expression
if(DEFINED CACHE{someName}) will only evaluate to true if a
cache variable someName exists. Both expressions need to
be tested if you need to know whether a non-cache variable
exists: if(DEFINED someName AND NOT DEFINED
CACHE{someName}).
Added in version 3.14: Added support for CACHE{<name>}
variables.
if(<variable|string> IN_LIST <variable>)
Added in version 3.3.
True if the given element is contained in the named list
variable.
File Operations
if(EXISTS <path-to-file-or-directory>)
True if the named file or directory exists and is readable.
Behavior is well-defined only for explicit full paths (a leading
~/ is not expanded as a home directory and is considered a
relative path). Resolves symbolic links, i.e. if the named file
or directory is a symbolic link, returns true if the target of
the symbolic link exists.
False if the given path is an empty string.
Note:
Prefer if(IS_READABLE) to check file readability. if(EXISTS)
may be changed in the future to only check file existence.
if(IS_READABLE <path-to-file-or-directory>)
Added in version 3.29.
True if the named file or directory is readable. Behavior is
well-defined only for explicit full paths (a leading ~/ is not
expanded as a home directory and is considered a relative path).
Resolves symbolic links, i.e. if the named file or directory is
a symbolic link, returns true if the target of the symbolic link
is readable.
False if the given path is an empty string.
if(IS_WRITABLE <path-to-file-or-directory>)
Added in version 3.29.
True if the named file or directory is writable. Behavior is
well-defined only for explicit full paths (a leading ~/ is not
expanded as a home directory and is considered a relative path).
Resolves symbolic links, i.e. if the named file or directory is
a symbolic link, returns true if the target of the symbolic link
is writable.
False if the given path is an empty string.
if(IS_EXECUTABLE <path-to-file-or-directory>)
Added in version 3.29.
True if the named file or directory is executable. Behavior is
well-defined only for explicit full paths (a leading ~/ is not
expanded as a home directory and is considered a relative path).
Resolves symbolic links, i.e. if the named file or directory is
a symbolic link, returns true if the target of the symbolic link
is executable.
False if the given path is an empty string.
if(<file1> IS_NEWER_THAN <file2>)
True if file1 is newer than file2 or if one of the two files
doesn't exist. Behavior is well-defined only for full paths.
If the file time stamps are exactly the same, an IS_NEWER_THAN
comparison returns true, so that any dependent build operations
will occur in the event of a tie. This includes the case of
passing the same file name for both file1 and file2.
if(IS_DIRECTORY <path>)
True if path is a directory. Behavior is well-defined only for
full paths.
False if the given path is an empty string.
if(IS_SYMLINK <path>)
True if the given path is a symbolic link. Behavior is
well-defined only for full paths.
if(IS_ABSOLUTE <path>)
True if the given path is an absolute path. Note the following
special cases:
o An empty path evaluates to false.
o On Windows hosts, any path that begins with a drive letter and
colon (e.g. C:), a forward slash or a backslash will evaluate
to true. This means a path like C:no\base\dir will evaluate
to true, even though the non-drive part of the path is
relative.
o On non-Windows hosts, any path that begins with a tilde (~)
evaluates to true.
Comparisons
if(<variable|string> MATCHES <regex>)
True if the given string or variable's value matches the given
regular expression. See Regex Specification <#regex-
specification> for regex format.
Added in version 3.9: () groups are captured in CMAKE_MATCH_<n>
<#variable:CMAKE_MATCH_<n>> variables.
if(<variable|string> LESS <variable|string>)
True if the given string or variable's value parses as a real
number (like a C double) and less than that on the right.
if(<variable|string> GREATER <variable|string>)
True if the given string or variable's value parses as a real
number (like a C double) and greater than that on the right.
if(<variable|string> EQUAL <variable|string>)
True if the given string or variable's value parses as a real
number (like a C double) and equal to that on the right.
if(<variable|string> LESS_EQUAL <variable|string>)
Added in version 3.7.
True if the given string or variable's value parses as a real
number (like a C double) and less than or equal to that on the
right.
if(<variable|string> GREATER_EQUAL <variable|string>)
Added in version 3.7.
True if the given string or variable's value parses as a real
number (like a C double) and greater than or equal to that on
the right.
if(<variable|string> STRLESS <variable|string>)
True if the given string or variable's value is
lexicographically less than the string or variable on the right.
if(<variable|string> STRGREATER <variable|string>)
True if the given string or variable's value is
lexicographically greater than the string or variable on the
right.
if(<variable|string> STREQUAL <variable|string>)
True if the given string or variable's value is
lexicographically equal to the string or variable on the right.
if(<variable|string> STRLESS_EQUAL <variable|string>)
Added in version 3.7.
True if the given string or variable's value is
lexicographically less than or equal to the string or variable
on the right.
if(<variable|string> STRGREATER_EQUAL <variable|string>)
Added in version 3.7.
True if the given string or variable's value is
lexicographically greater than or equal to the string or
variable on the right.
Version Comparisons
if(<variable|string> VERSION_LESS <variable|string>)
Component-wise integer version number comparison (version format
is major[.minor[.patch[.tweak]]], omitted components are treated
as zero). Any non-integer version component or non-integer
trailing part of a version component effectively truncates the
string at that point.
if(<variable|string> VERSION_GREATER <variable|string>)
Component-wise integer version number comparison (version format
is major[.minor[.patch[.tweak]]], omitted components are treated
as zero). Any non-integer version component or non-integer
trailing part of a version component effectively truncates the
string at that point.
if(<variable|string> VERSION_EQUAL <variable|string>)
Component-wise integer version number comparison (version format
is major[.minor[.patch[.tweak]]], omitted components are treated
as zero). Any non-integer version component or non-integer
trailing part of a version component effectively truncates the
string at that point.
if(<variable|string> VERSION_LESS_EQUAL <variable|string>)
Added in version 3.7.
Component-wise integer version number comparison (version format
is major[.minor[.patch[.tweak]]], omitted components are treated
as zero). Any non-integer version component or non-integer
trailing part of a version component effectively truncates the
string at that point.
if(<variable|string> VERSION_GREATER_EQUAL <variable|string>)
Added in version 3.7.
Component-wise integer version number comparison (version format
is major[.minor[.patch[.tweak]]], omitted components are treated
as zero). Any non-integer version component or non-integer
trailing part of a version component effectively truncates the
string at that point.
Path Comparisons
if(<variable|string> PATH_EQUAL <variable|string>)
Added in version 3.24.
Compares the two paths component-by-component. Only if every
component of both paths match will the two paths compare equal.
Multiple path separators are effectively collapsed into a single
separator, but note that backslashes are not converted to
forward slashes. No other path normalization <#normalization>
is performed.
Component-wise comparison is superior to string-based comparison
due to the handling of multiple path separators. In the
following example, the expression evaluates to true using
PATH_EQUAL, but false with STREQUAL:
# comparison is TRUE
if ("/a//b/c" PATH_EQUAL "/a/b/c")
...
endif()
# comparison is FALSE
if ("/a//b/c" STREQUAL "/a/b/c")
...
endif()
See cmake_path(COMPARE) <#path-compare> for more details.
Variable Expansion
The if command was written very early in CMake's history, predating the
${} variable evaluation syntax, and for convenience evaluates variables
named by its arguments as shown in the above signatures. Note that
normal variable evaluation with ${} applies before the if command even
receives the arguments. Therefore code like
set(var1 OFF)
set(var2 "var1")
if(${var2})
appears to the if command as
if(var1)
and is evaluated according to the if(<variable>) case documented above.
The result is OFF which is false. However, if we remove the ${} from
the example then the command sees
if(var2)
which is true because var2 is defined to var1 which is not a false
constant.
Automatic evaluation applies in the other cases whenever the
above-documented condition syntax accepts <variable|string>:
o The left hand argument to MATCHES is first checked to see if it is a
defined variable. If so, the variable's value is used, otherwise the
original value is used.
o If the left hand argument to MATCHES is missing it returns false
without error
o Both left and right hand arguments to LESS, GREATER, EQUAL,
LESS_EQUAL, and GREATER_EQUAL, are independently tested to see if
they are defined variables. If so, their defined values are used
otherwise the original value is used.
o Both left and right hand arguments to STRLESS, STRGREATER, STREQUAL,
STRLESS_EQUAL, and STRGREATER_EQUAL are independently tested to see
if they are defined variables. If so, their defined values are used
otherwise the original value is used.
o Both left and right hand arguments to VERSION_LESS, VERSION_GREATER,
VERSION_EQUAL, VERSION_LESS_EQUAL, and VERSION_GREATER_EQUAL are
independently tested to see if they are defined variables. If so,
their defined values are used otherwise the original value is used.
o The left hand argument to IN_LIST is tested to see if it is a defined
variable. If so, the variable's value is used, otherwise the
original value is used.
o The right hand argument to NOT is tested to see if it is a boolean
constant. If so, the value is used, otherwise it is assumed to be a
variable and it is dereferenced.
o The left and right hand arguments to AND and OR are independently
tested to see if they are boolean constants. If so, they are used as
such, otherwise they are assumed to be variables and are
dereferenced.
Changed in version 3.1: To prevent ambiguity, potential variable or
keyword names can be specified in a Quoted Argument <#quoted-argument>
or a Bracket Argument <#bracket-argument>. A quoted or bracketed
variable or keyword will be interpreted as a string and not
dereferenced or interpreted. See policy CMP0054 <#policy:CMP0054>.
There is no automatic evaluation for environment or cache Variable
References <#variable-references>. Their values must be referenced as
$ENV{<name>} or $CACHE{<name>} wherever the above-documented condition
syntax accepts <variable|string>.
See also
o else() <#command:else>
o elseif() <#command:elseif>
o endif() <#command:endif>
include
Load and run CMake code from a file or module.
include(<file|module> [OPTIONAL] [RESULT_VARIABLE <var>]
[NO_POLICY_SCOPE])
Loads and runs CMake code from the file given. Variable reads and
writes access the scope of the caller (dynamic scoping). If OPTIONAL
is present, then no error is raised if the file does not exist. If
RESULT_VARIABLE is given the variable <var> will be set to the full
filename which has been included or NOTFOUND if it failed.
If a module is specified instead of a file, the file with name
<modulename>.cmake is searched first in CMAKE_MODULE_PATH <#
variable:CMAKE_MODULE_PATH>, then in the CMake module directory. There
is one exception to this: if the file which calls include() is located
itself in the CMake builtin module directory, then first the CMake
builtin module directory is searched and CMAKE_MODULE_PATH <#
variable:CMAKE_MODULE_PATH> afterwards. See also policy CMP0017 <#
policy:CMP0017>.
See the cmake_policy() <#command:cmake_policy> command documentation
for discussion of the NO_POLICY_SCOPE option.
include_guard
Added in version 3.10.
Provides an include guard for the file currently being processed by
CMake.
include_guard([DIRECTORY|GLOBAL])
Sets up an include guard for the current CMake file (see the
CMAKE_CURRENT_LIST_FILE <#variable:CMAKE_CURRENT_LIST_FILE> variable
documentation).
CMake will end its processing of the current file at the location of
the include_guard command if the current file has already been
processed for the applicable scope (see below). This provides
functionality similar to the include guards commonly used in source
processed previously for the applicable scope, the effect is as though
return() <#command:return> had been called. Do not call this command
from inside a function being defined within the current file.
An optional argument specifying the scope of the guard may be provided.
Possible values for the option are:
DIRECTORY
The include guard applies within the current directory and
below. The file will only be included once within this directory
scope, but may be included again by other files outside of this
directory (i.e. a parent directory or another directory not
pulled in by add_subdirectory() <#command:add_subdirectory> or
include() <#command:include> from the current file or its
children).
GLOBAL The include guard applies globally to the whole build. The
current file will only be included once regardless of the scope.
If no arguments given, include_guard has the same scope as a variable,
meaning that the include guard effect is isolated by the most recent
function scope or current directory if no inner function scopes exist.
In this case the command behavior is the same as:
if(__CURRENT_FILE_VAR__)
return()
endif()
set(__CURRENT_FILE_VAR__ TRUE)
list
Operations on semicolon-separated lists <#cmake-language-lists>.
Synopsis
Reading
list(LENGTH <list> <out-var>)
list(GET <list> <element index> [<index> ...] <out-var>)
list(JOIN <list> <glue> <out-var>)
list(SUBLIST <list> <begin> <length> <out-var>)
Search
list(FIND <list> <value> <out-var>)
Modification
list(APPEND <list> [<element>...])
list(FILTER <list> {INCLUDE | EXCLUDE} REGEX <regex>)
list(INSERT <list> <index> [<element>...])
list(POP_BACK <list> [<out-var>...])
list(POP_FRONT <list> [<out-var>...])
list(PREPEND <list> [<element>...])
list(REMOVE_ITEM <list> <value>...)
list(REMOVE_AT <list> <index>...)
list(REMOVE_DUPLICATES <list>)
list(TRANSFORM <list> <ACTION> [...])
Ordering
list(REVERSE <list>)
list(SORT <list> [...])
Introduction
The list subcommands APPEND, INSERT, FILTER, PREPEND, POP_BACK,
POP_FRONT, REMOVE_AT, REMOVE_ITEM, REMOVE_DUPLICATES, REVERSE and SORT
may create new values for the list within the current CMake variable
scope. Similar to the set() <#command:set> command, the list command
creates new variable values in the current scope, even if the list
itself is actually defined in a parent scope. To propagate the results
of these operations upwards, use set() <#command:set> with
PARENT_SCOPE, set() <#command:set> with CACHE INTERNAL, or some other
means of value propagation.
Note:
A list in cmake is a ; separated group of strings. To create a
list, the set() <#command:set> command can be used. For example,
set(var a b c d e) creates a list with a;b;c;d;e, and set(var "a b c
d e") creates a string or a list with one item in it. (Note that
macro arguments are not variables, and therefore cannot be used in
LIST commands.)
Individual elements may not contain an unequal number of [ and ]
characters, and may not end in a backslash (\). See
semicolon-separated lists <#cmake-language-lists> for details.
Note:
When specifying index values, if <element index> is 0 or greater, it
is indexed from the beginning of the list, with 0 representing the
first list element. If <element index> is -1 or lesser, it is
indexed from the end of the list, with -1 representing the last list
element. Be careful when counting with negative indices: they do
not start from 0. -0 is equivalent to 0, the first list element.
Reading
list(LENGTH <list> <output variable>)
Returns the list's length.
list(GET <list> <element index> [<element index> ...]
<output variable>)
Returns the list of elements specified by indices from the list.
list(JOIN <list> <glue> <output variable>)
Added in version 3.12.
Returns a string joining all list's elements using the glue
string. To join multiple strings, which are not part of a list,
use string(JOIN) <#join>.
list(SUBLIST <list> <begin> <length> <output variable>)
Added in version 3.12.
Returns a sublist of the given list. If <length> is 0, an empty
list will be returned. If <length> is -1 or the list is smaller
than <begin>+<length> then the remaining elements of the list
starting at <begin> will be returned.
Search
list(FIND <list> <value> <output variable>)
Returns the index of the element specified in the list or -1 if
it wasn't found.
Modification
list(APPEND <list> [<element> ...])
Appends elements to the list. If no variable named <list> exists
in the current scope its value is treated as empty and the
elements are appended to that empty list.
list(FILTER <list> <INCLUDE|EXCLUDE> REGEX <regular_expression>)
Added in version 3.6.
Includes or removes items from the list that match the mode's pattern.
In REGEX mode, items will be matched against the given regular
expression.
For more information on regular expressions look under string(REGEX) <#
regex-specification>.
list(INSERT <list> <element_index> <element> [<element> ...])
Inserts elements to the list to the specified index. It is an
error to specify an out-of-range index. Valid indexes are 0 to N
where N is the length of the list, inclusive. An empty list has
length 0. If no variable named <list> exists in the current
scope its value is treated as empty and the elements are
inserted in that empty list.
list(POP_BACK <list> [<out-var>...])
Added in version 3.15.
If no variable name is given, removes exactly one element.
Otherwise, with N variable names provided, assign the last N
elements' values to the given variables and then remove the last
N values from <list>.
list(POP_FRONT <list> [<out-var>...])
Added in version 3.15.
If no variable name is given, removes exactly one element.
Otherwise, with N variable names provided, assign the first N
elements' values to the given variables and then remove the
first N values from <list>.
list(PREPEND <list> [<element> ...])
Added in version 3.15.
Insert elements to the 0th position in the list. If no variable
named <list> exists in the current scope its value is treated as
empty and the elements are prepended to that empty list.
list(REMOVE_ITEM <list> <value> [<value> ...])
Removes all instances of the given items from the list.
list(REMOVE_AT <list> <index> [<index> ...])
Removes items at given indices from the list.
list(REMOVE_DUPLICATES <list>)
Removes duplicated items in the list. The relative order of
items is preserved, but if duplicates are encountered, only the
first instance is preserved.
list(TRANSFORM <list> <ACTION> [<SELECTOR>]
[OUTPUT_VARIABLE <output variable>])
Added in version 3.12.
Transforms the list by applying an <ACTION> to all or, by
specifying a <SELECTOR>, to the selected elements of the list,
storing the result in-place or in the specified output variable.
Note:
The TRANSFORM sub-command does not change the number of
elements in the list. If a <SELECTOR> is specified, only some
elements will be changed, the other ones will remain the same
as before the transformation.
<ACTION> specifies the action to apply to the elements of the
list. The actions have exactly the same semantics as
sub-commands of the string() <#command:string> command.
<ACTION> must be one of the following:
APPEND <#append>, PREPEND <#prepend>
Append, prepend specified value to each element of the
list.
list(TRANSFORM <list> (APPEND|PREPEND) <value> ...)
TOLOWER <#tolower>, TOUPPER <#toupper>
Convert each element of the list to lower, upper
characters.
list(TRANSFORM <list> (TOLOWER|TOUPPER) ...)
STRIP <#strip>
Remove leading and trailing spaces from each element
of the list.
list(TRANSFORM <list> STRIP ...)
GENEX_STRIP <#genex-strip>
Strip any generator expressions <#manual:cmake-
generator-expressions(7)> from each element of the
list.
list(TRANSFORM <list> GENEX_STRIP ...)
REPLACE <#regex-replace>:
Match the regular expression as many times as possible
and substitute the replacement expression for the
match for each element of the list (same semantic as
string(REGEX REPLACE) <#regex-replace>).
list(TRANSFORM <list> REPLACE <regular_expression>
<replace_expression> ...)
<SELECTOR> determines which elements of the list will be
transformed. Only one type of selector can be specified at a
time. When given, <SELECTOR> must be one of the following:
AT Specify a list of indexes.
list(TRANSFORM <list> <ACTION> AT <index> [<index> ...] ...)
FOR Specify a range with, optionally, an increment used to
iterate over the range.
list(TRANSFORM <list> <ACTION> FOR <start> <stop> [<step>] ...)
REGEX Specify a regular expression. Only elements matching
the regular expression will be transformed.
list(TRANSFORM <list> <ACTION> REGEX <regular_expression> ...)
Ordering
list(REVERSE <list>)
Reverses the contents of the list in-place.
list(SORT <list> [COMPARE <compare>] [CASE <case>] [ORDER <order>])
Sorts the list in-place alphabetically.
Added in version 3.13: Added the COMPARE, CASE, and ORDER
options.
Added in version 3.18: Added the COMPARE NATURAL option.
Use the COMPARE keyword to select the comparison method for
sorting. The <compare> option should be one of:
STRING Sorts a list of strings alphabetically. This is the
default behavior if the COMPARE option is not given.
FILE_BASENAME
Sorts a list of pathnames of files by their basenames.
NATURAL
Sorts a list of strings using natural order (see
strverscmp(3) manual), i.e. such that contiguous
digits are compared as whole numbers. For example:
the following list 10.0 1.1 2.1 8.0 2.0 3.1 will be
sorted as 1.1 2.0 2.1 3.1 8.0 10.0 if the NATURAL
comparison is selected where it will be sorted as 1.1
10.0 2.0 2.1 3.1 8.0 with the STRING comparison.
Use the CASE keyword to select a case sensitive or case
insensitive sort mode. The <case> option should be one of:
SENSITIVE
List items are sorted in a case-sensitive manner.
This is the default behavior if the CASE option is not
given.
INSENSITIVE
List items are sorted case insensitively. The order
of items which differ only by upper/lowercase is not
specified.
To control the sort order, the ORDER keyword can be given. The
<order> option should be one of:
ASCENDING
Sorts the list in ascending order. This is the
default behavior when the ORDER option is not given.
DESCENDING
Sorts the list in descending order.
macro
Start recording a macro for later invocation as a command
macro(<name> [<arg1> ...])
<commands>
endmacro()
Defines a macro named <name> that takes arguments named <arg1>, ...
Commands listed after macro, but before the matching endmacro() <#
command:endmacro>, are not executed until the macro is invoked.
Per legacy, the endmacro() <#command:endmacro> command admits an
optional <name> argument. If used, it must be a verbatim repeat of the
argument of the opening macro command.
See the cmake_policy() <#command:cmake_policy> command documentation
for the behavior of policies inside macros.
See the Macro vs Function section below for differences between CMake
macros and functions <#command:function>.
Invocation
The macro invocation is case-insensitive. A macro defined as
macro(foo)
<commands>
endmacro()
can be invoked through any of
foo()
Foo()
FOO()
cmake_language(CALL foo)
and so on. However, it is strongly recommended to stay with the case
chosen in the macro definition. Typically macros use all-lowercase
names.
Added in version 3.18: The cmake_language(CALL ...) <#
command:cmake_language> command can also be used to invoke the macro.
Arguments
When a macro is invoked, the commands recorded in the macro are first
modified by replacing formal parameters (${arg1}, ...) with the
arguments passed, and then invoked as normal commands.
In addition to referencing the formal parameters you can reference the
values ${ARGC} which will be set to the number of arguments passed into
the macro as well as ${ARGV0}, ${ARGV1}, ${ARGV2}, ... which will have
the actual values of the arguments passed in. This facilitates
creating macros with optional arguments.
Furthermore, ${ARGV} holds the list of all arguments given to the macro
and ${ARGN} holds the list of arguments past the last expected
argument. Referencing to ${ARGV#} arguments beyond ${ARGC} have
undefined behavior. Checking that ${ARGC} is greater than # is the only
way to ensure that ${ARGV#} was passed to the function as an extra
argument.
Macro vs Function
The macro command is very similar to the function() <#command:function>
command. Nonetheless, there are a few important differences.
In a function, ARGN, ARGC, ARGV and ARGV0, ARGV1, ... are true
variables in the usual CMake sense. In a macro, they are not, they are
string replacements much like the C preprocessor would do with a macro.
This has a number of consequences, as explained in the Argument Caveats
section below.
Another difference between macros and functions is the control flow. A
function is executed by transferring control from the calling statement
to the function body. A macro is executed as if the macro body were
pasted in place of the calling statement. This has the consequence
that a return() <#command:return> in a macro body does not just
terminate execution of the macro; rather, control is returned from the
scope of the macro call. To avoid confusion, it is recommended to
avoid return() <#command:return> in macros altogether.
Unlike a function, the CMAKE_CURRENT_FUNCTION <#
variable:CMAKE_CURRENT_FUNCTION>, CMAKE_CURRENT_FUNCTION_LIST_DIR <#
variable:CMAKE_CURRENT_FUNCTION_LIST_DIR>,
CMAKE_CURRENT_FUNCTION_LIST_FILE <#
variable:CMAKE_CURRENT_FUNCTION_LIST_FILE>,
CMAKE_CURRENT_FUNCTION_LIST_LINE <#
variable:CMAKE_CURRENT_FUNCTION_LIST_LINE> variables are not set for a
macro.
Argument Caveats
Since ARGN, ARGC, ARGV, ARGV0 etc. are not variables, you will NOT be
able to use commands like
if(ARGV1) # ARGV1 is not a variable
if(DEFINED ARGV2) # ARGV2 is not a variable
if(ARGC GREATER 2) # ARGC is not a variable
foreach(loop_var IN LISTS ARGN) # ARGN is not a variable
In the first case, you can use if(${ARGV1}). In the second and third
case, the proper way to check if an optional variable was passed to the
macro is to use if(${ARGC} GREATER 2). In the last case, you can use
foreach(loop_var ${ARGN}) but this will skip empty arguments. If you
need to include them, you can use
set(list_var "${ARGN}")
foreach(loop_var IN LISTS list_var)
Note that if you have a variable with the same name in the scope from
which the macro is called, using unreferenced names will use the
existing variable instead of the arguments. For example:
macro(bar)
foreach(arg IN LISTS ARGN)
<commands>
endforeach()
endmacro()
function(foo)
bar(x y z)
endfunction()
foo(a b c)
Will loop over a;b;c and not over x;y;z as one might have expected. If
you want true CMake variables and/or better CMake scope control you
should look at the function command.
See Also
o cmake_parse_arguments() <#command:cmake_parse_arguments>
o endmacro() <#command:endmacro>
mark_as_advanced
Mark cmake cached variables as advanced.
mark_as_advanced([CLEAR|FORCE] <var1> ...)
Sets the advanced/non-advanced state of the named cached variables.
An advanced variable will not be displayed in any of the cmake GUIs
unless the show advanced option is on. In script mode, the
advanced/non-advanced state has no effect.
If the keyword CLEAR is given then advanced variables are changed back
to unadvanced. If the keyword FORCE is given then the variables are
made advanced. If neither FORCE nor CLEAR is specified, new values
will be marked as advanced, but if a variable already has an
advanced/non-advanced state, it will not be changed.
Changed in version 3.17: Variables passed to this command which are not
already in the cache are ignored. See policy CMP0102 <#policy:CMP0102>.
math
Evaluate a mathematical expression.
math(EXPR <variable> "<expression>" [OUTPUT_FORMAT <format>])
Evaluates a mathematical <expression> and sets <variable> to the
resulting value. The result of the expression must be representable as
a 64-bit signed integer. Floating point inputs are invalid e.g. 1.1 *
10. Non-integer results e.g. 3 / 2 are truncated.
The mathematical expression must be given as a string (i.e. enclosed in
double quotation marks). An example is "5 * (10 + 13)". Supported
operators are +, -, *, /, %, |, &, ^, ~, <<, >>, and (...); they have
the same meaning as in C code.
Added in version 3.13: Hexadecimal numbers are recognized when prefixed
with 0x, as in C code.
Added in version 3.13: The result is formatted according to the option
OUTPUT_FORMAT, where <format> is one of
HEXADECIMAL
Hexadecimal notation as in C code, i. e. starting with "0x".
DECIMAL
Decimal notation. Which is also used if no OUTPUT_FORMAT option
is specified.
For example
math(EXPR value "100 * 0xA" OUTPUT_FORMAT DECIMAL) # value is set to "1000"
math(EXPR value "100 * 0xA" OUTPUT_FORMAT HEXADECIMAL) # value is set to "0x3e8"
message
Log a message.
Synopsis
General messages
message([<mode>] "message text" ...)
Reporting checks
message(<checkState> "message text" ...)
Configure Log
message(CONFIGURE_LOG <text>...)
General messages
message([<mode>] "message text" ...)
Record the specified message text in the log. If more than one message
string is given, they are concatenated into a single message with no
separator between the strings.
The optional <mode> keyword determines the type of message, which
influences the way the message is handled:
FATAL_ERROR
CMake Error, stop processing and generation.
The cmake(1) <#manual:cmake(1)> executable will return a
non-zero exit code <#cmake-exit-code>.
SEND_ERROR
CMake Error, continue processing, but skip generation.
WARNING
CMake Warning, continue processing.
AUTHOR_WARNING
CMake Warning (dev), continue processing.
DEPRECATION
CMake Deprecation Error or Warning if variable
CMAKE_ERROR_DEPRECATED <#variable:CMAKE_ERROR_DEPRECATED> or
CMAKE_WARN_DEPRECATED <#variable:CMAKE_WARN_DEPRECATED> is
enabled, respectively, else no message.
(none) or NOTICE
Important message printed to stderr to attract user's attention.
STATUS The main interesting messages that project users might be
interested in. Ideally these should be concise, no more than a
single line, but still informative.
VERBOSE
Detailed informational messages intended for project users.
These messages should provide additional details that won't be
of interest in most cases, but which may be useful to those
building the project when they want deeper insight into what's
happening.
DEBUG Detailed informational messages intended for developers working
on the project itself as opposed to users who just want to build
it. These messages will not typically be of interest to other
users building the project and will often be closely related to
internal implementation details.
TRACE Fine-grained messages with very low-level implementation
details. Messages using this log level would normally only be
temporary and would expect to be removed before releasing the
project, packaging up the files, etc.
Added in version 3.15: Added the NOTICE, VERBOSE, DEBUG, and TRACE
levels.
The CMake command-line tool displays STATUS to TRACE messages on stdout
with the message preceded by two hyphens and a space. All other
message types are sent to stderr and are not prefixed with hyphens.
The CMake GUI <#manual:cmake-gui(1)> displays all messages in its log
area. The curses interface <#manual:ccmake(1)> shows STATUS to TRACE
messages one at a time on a status line and other messages in an
interactive pop-up box. The --log-level <#cmdoption-cmake-log-level>
command-line option to each of these tools can be used to control which
messages will be shown.
Added in version 3.17: To make a log level persist between CMake runs,
the CMAKE_MESSAGE_LOG_LEVEL <#variable:CMAKE_MESSAGE_LOG_LEVEL>
variable can be set instead. Note that the command line option takes
precedence over the cache variable.
Added in version 3.16: Messages of log levels NOTICE and below will
have each line preceded by the content of the CMAKE_MESSAGE_INDENT <#
variable:CMAKE_MESSAGE_INDENT> variable (converted to a single string
by concatenating its list items). For STATUS to TRACE messages, this
indenting content will be inserted after the hyphens.
Added in version 3.17: Messages of log levels NOTICE and below can also
have each line preceded with context of the form
[some.context.example]. The content between the square brackets is
obtained by converting the CMAKE_MESSAGE_CONTEXT <#
variable:CMAKE_MESSAGE_CONTEXT> list variable to a dot-separated
string. The message context will always appear before any indenting
content but after any automatically added leading hyphens. By default,
message context is not shown, it has to be explicitly enabled by giving
the cmake --log-context <#cmdoption-cmake-log-context> command-line
option or by setting the CMAKE_MESSAGE_CONTEXT_SHOW <#
variable:CMAKE_MESSAGE_CONTEXT_SHOW> variable to true. See the
CMAKE_MESSAGE_CONTEXT <#variable:CMAKE_MESSAGE_CONTEXT> documentation
for usage examples.
CMake Warning and Error message text displays using a simple markup
language. Non-indented text is formatted in line-wrapped paragraphs
delimited by newlines. Indented text is considered pre-formatted.
Reporting checks
Added in version 3.17.
A common pattern in CMake output is a message indicating the start of
some sort of check, followed by another message reporting the result of
that check. For example:
message(STATUS "Looking for someheader.h")
#... do the checks, set checkSuccess with the result
if(checkSuccess)
message(STATUS "Looking for someheader.h - found")
else()
message(STATUS "Looking for someheader.h - not found")
endif()
This can be more robustly and conveniently expressed using the
CHECK_... keyword form of the message() command:
message(<checkState> "message" ...)
where <checkState> must be one of the following:
CHECK_START
Record a concise message about the check about to be
performed.
CHECK_PASS
Record a successful result for a check.
CHECK_FAIL
Record an unsuccessful result for a check.
When recording a check result, the command repeats the message from the
most recently started check for which no result has yet been reported,
then some separator characters and then the message text provided after
the CHECK_PASS or CHECK_FAIL keyword. Check messages are always
reported at STATUS log level.
Checks may be nested and every CHECK_START should have exactly one
matching CHECK_PASS or CHECK_FAIL. The CMAKE_MESSAGE_INDENT <#
variable:CMAKE_MESSAGE_INDENT> variable can also be used to add
indenting to nested checks if desired. For example:
message(CHECK_START "Finding my things")
list(APPEND CMAKE_MESSAGE_INDENT " ")
unset(missingComponents)
message(CHECK_START "Finding partA")
# ... do check, assume we find A
message(CHECK_PASS "found")
message(CHECK_START "Finding partB")
# ... do check, assume we don't find B
list(APPEND missingComponents B)
message(CHECK_FAIL "not found")
list(POP_BACK CMAKE_MESSAGE_INDENT)
if(missingComponents)
message(CHECK_FAIL "missing components: ${missingComponents}")
else()
message(CHECK_PASS "all components found")
endif()
Output from the above would appear something like the following:
-- Finding my things
-- Finding partA
-- Finding partA - found
-- Finding partB
-- Finding partB - not found
-- Finding my things - missing components: B
Configure Log
Added in version 3.26.
message(CONFIGURE_LOG <text>...)
Record a configure-log message event <#message-configure-log-event>
with the specified <text>. By convention, if the text contains more
than one line, the first line should be a summary of the event.
This mode is intended to record the details of a system inspection
check or other one-time operation guarded by a cache entry, but that is
not performed using try_compile() <#command:try_compile> or try_run()
<#command:try_run>, which automatically log their details. Projects
should avoid calling it every time CMake runs. For example:
if (NOT DEFINED MY_CHECK_RESULT)
# Print check summary in configure output.
message(CHECK_START "My Check")
# ... perform system inspection, e.g., with execute_process ...
# Cache the result so we do not run the check again.
set(MY_CHECK_RESULT "${MY_CHECK_RESULT}" CACHE INTERNAL "My Check")
# Record the check details in the cmake-configure-log.
message(CONFIGURE_LOG
"My Check Result: ${MY_CHECK_RESULT}\n"
"${details}"
)
# Print check result in configure output.
if(MY_CHECK_RESULT)
message(CHECK_PASS "passed")
else()
message(CHECK_FAIL "failed")
endif()
endif()
If no project is currently being configured, such as in cmake -P <#
script-processing-mode> script mode, this command does nothing.
See Also
o cmake_language(GET_MESSAGE_LOG_LEVEL) <#get-message-log-level>
option
Provide a boolean option that the user can optionally select.
option(<variable> "<help_text>" [value])
If no initial <value> is provided, boolean OFF is the default value.
If <variable> is already set as a normal or cache variable, then the
command does nothing (see policy CMP0077 <#policy:CMP0077>).
For options that depend on the values of other options, see the module
help for CMakeDependentOption <#module:CMakeDependentOption>.
In CMake project mode, a boolean cache variable is created with the
option value. In CMake script mode, a boolean variable is set with the
option value.
return
Return from a file, directory or function.
return([PROPAGATE <var-name>...])
When this command is encountered in an included file (via include() <#
command:include> or find_package() <#command:find_package>), it causes
processing of the current file to stop and control is returned to the
including file. If it is encountered in a file which is not included
by another file, e.g. a CMakeLists.txt, deferred calls scheduled by
cmake_language(DEFER) <#defer> are invoked and control is returned to
the parent directory if there is one.
If return() is called in a function, control is returned to the caller
of that function. Note that a macro() <#command:macro>, unlike a
function() <#command:function>, is expanded in place and therefore
cannot handle return().
Policy CMP0140 <#policy:CMP0140> controls the behavior regarding the
arguments of the command. All arguments are ignored unless that policy
is set to NEW.
PROPAGATE
Added in version 3.25.
This option sets or unsets the specified variables in the parent
directory or function caller scope. This is equivalent to
set(PARENT_SCOPE) <#command:set> or unset(PARENT_SCOPE) <#
command:unset> commands, except for the way it interacts with
the block() <#command:block> command, as described below.
The PROPAGATE option can be very useful in conjunction with the
block() <#command:block> command. A return will propagate the
specified variables through any enclosing block scopes created
by the block() <#command:block> commands. Inside a function,
this ensures the variables are propagated to the function's
caller, regardless of any blocks within the function. If not
inside a function, it ensures the variables are propagated to
the parent file or directory scope. For example:
CMakeLists.txt
cmake_minimum_required(VERSION 3.25)
project(example)
set(var1 "top-value")
block(SCOPE_FOR VARIABLES)
add_subdirectory(subDir)
# var1 has the value "block-nested"
endblock()
# var1 has the value "top-value"
subDir/CMakeLists.txt
function(multi_scopes result_var1 result_var2)
block(SCOPE_FOR VARIABLES)
# This would only propagate out of the immediate block, not to
# the caller of the function.
#set(${result_var1} "new-value" PARENT_SCOPE)
#unset(${result_var2} PARENT_SCOPE)
# This propagates the variables through the enclosing block and
# out to the caller of the function.
set(${result_var1} "new-value")
unset(${result_var2})
return(PROPAGATE ${result_var1} ${result_var2})
endblock()
endfunction()
set(var1 "some-value")
set(var2 "another-value")
multi_scopes(var1 var2)
# Now var1 will hold "new-value" and var2 will be unset
block(SCOPE_FOR VARIABLES)
# This return() will set var1 in the directory scope that included us
# via add_subdirectory(). The surrounding block() here does not limit
# propagation to the current file, but the block() in the parent
# directory scope does prevent propagation going any further.
set(var1 "block-nested")
return(PROPAGATE var1)
endblock()
See Also
o block() <#command:block>
o function() <#command:function>
separate_arguments
Parse command-line arguments into a semicolon-separated list.
separate_arguments(<variable> <mode> [PROGRAM [SEPARATE_ARGS]] <args>)
Parses a space-separated string <args> into a list of items, and stores
this list in semicolon-separated standard form in <variable>.
This function is intended for parsing command-line arguments. The
entire command line must be passed as one string in the argument
<args>.
The exact parsing rules depend on the operating system. They are
specified by the <mode> argument which must be one of the following
keywords:
UNIX_COMMAND
Arguments are separated by unquoted whitespace. Both
single-quote and double-quote pairs are respected. A backslash
escapes the next literal character (\" is "); there are no
special escapes (\n is just n).
WINDOWS_COMMAND
A Windows command-line is parsed using the same syntax the
runtime library uses to construct argv at startup. It separates
arguments by whitespace that is not double-quoted. Backslashes
are literal unless they precede double-quotes. See the MSDN
article Parsing C Command-Line Arguments <https://learn
.microsoft.com/en-us/cpp/c-language/parsing-c-command-line-
arguments> for details.
NATIVE_COMMAND
Added in version 3.9.
Proceeds as in WINDOWS_COMMAND mode if the host system is
Windows. Otherwise proceeds as in UNIX_COMMAND mode.
PROGRAM
Added in version 3.19.
The first item in <args> is assumed to be an executable and will
be searched in the system search path or left as a full path. If
not found, <variable> will be empty. Otherwise, <variable> is a
list of 2 elements:
0. Absolute path of the program
1. Any command-line arguments present in <args> as a string
For example:
separate_arguments (out UNIX_COMMAND PROGRAM "cc -c main.c")
o First element of the list: /path/to/cc
o Second element of the list: " -c main.c"
SEPARATE_ARGS
When this sub-option of PROGRAM option is specified,
command-line arguments will be split as well and stored in
<variable>.
For example:
separate_arguments (out UNIX_COMMAND PROGRAM SEPARATE_ARGS "cc -c main.c")
The contents of out will be: /path/to/cc;-c;main.c
separate_arguments(<var>)
Convert the value of <var> to a semi-colon separated list. All spaces
are replaced with ';'. This helps with generating command lines.
set
Set a normal, cache, or environment variable to a given value. See the
cmake-language(7) variables <#cmake-language-variables> documentation
for the scopes and interaction of normal variables and cache entries.
Signatures of this command that specify a <value>... placeholder expect
zero or more arguments. Multiple arguments will be joined as a
semicolon-separated list <#cmake-language-lists> to form the actual
variable value to be set.
Set Normal Variable
set(<variable> <value>... [PARENT_SCOPE])
Set or unset <variable> in the current function or directory
scope:
o If at least one <value>... is given, set the variable to that
value.
o If no value is given, unset the variable. This is equivalent
to unset(<variable>) <#command:unset>.
If the PARENT_SCOPE option is given the variable will be set in
the scope above the current scope. Each new directory or
function() <#command:function> command creates a new scope. A
scope can also be created with the block() <#command:block>
command. set(PARENT_SCOPE) will set the value of a variable into
the parent directory, calling function, or encompassing scope
(whichever is applicable to the case at hand). The previous
state of the variable's value stays the same in the current
scope (e.g., if it was undefined before, it is still undefined
and if it had a value, it is still that value).
The block(PROPAGATE) <#command:block> and return(PROPAGATE) <#
command:return> commands can be used as an alternate method to
the set(PARENT_SCOPE) and unset(PARENT_SCOPE) <#command:unset>
commands to update the parent scope.
Note:
When evaluating Variable References <#variable-references> of the
form ${VAR}, CMake first searches for a normal variable with that
name. If no such normal variable exists, CMake will then search for
a cache entry with that name. Because of this, unsetting a normal
variable can expose a cache variable that was previously hidden. To
force a variable reference of the form ${VAR} to return an empty
string, use set(<variable> ""), which clears the normal variable but
leaves it defined.
Set Cache Entry
set(<variable> <value>... CACHE <type> <docstring> [FORCE])
Sets the given cache <variable> (cache entry). Since cache
entries are meant to provide user-settable values this does not
overwrite existing cache entries by default. Use the FORCE
option to overwrite existing entries.
The <type> must be specified as one of:
BOOL Boolean ON/OFF value. cmake-gui(1) <#manual:cmake-
gui(1)> offers a checkbox.
FILEPATH
Path to a file on disk. cmake-gui(1) <#manual:cmake-
gui(1)> offers a file dialog.
PATH Path to a directory on disk. cmake-gui(1) <#
manual:cmake-gui(1)> offers a file dialog.
STRING A line of text. cmake-gui(1) <#manual:cmake-gui(1)>
offers a text field or a drop-down selection if the
STRINGS <#prop_cache:STRINGS> cache entry property is
set.
INTERNAL
A line of text. cmake-gui(1) <#manual:cmake-gui(1)>
does not show internal entries. They may be used to
store variables persistently across runs. Use of this
type implies FORCE.
The <docstring> must be specified as a line of text providing a
quick summary of the option for presentation to cmake-gui(1) <#
manual:cmake-gui(1)> users.
If the cache entry does not exist prior to the call or the FORCE
option is given then the cache entry will be set to the given
value.
Note:
The content of the cache variable will not be directly
accessible if a normal variable of the same name already
exists (see rules of variable evaluation <#cmake-language-
variables>). If policy CMP0126 <#policy:CMP0126> is set to
OLD, any normal variable binding in the current scope will be
removed.
It is possible for the cache entry to exist prior to the call
but have no type set if it was created on the cmake(1) <#
manual:cmake(1)> command line by a user through the
-D<var>=<value> <#cmdoption-cmake-D> option without specifying a
type. In this case the set command will add the type.
Furthermore, if the <type> is PATH or FILEPATH and the <value>
provided on the command line is a relative path, then the set
command will treat the path as relative to the current working
directory and convert it to an absolute path.
Set Environment Variable
set(ENV{<variable>} [<value>])
Sets an Environment Variable <#manual:cmake-env-variables(7)> to
the given value. Subsequent calls of $ENV{<variable>} will
return this new value.
This command affects only the current CMake process, not the
process from which CMake was called, nor the system environment
at large, nor the environment of subsequent build or test
processes.
If no argument is given after ENV{<variable>} or if <value> is
an empty string, then this command will clear any existing value
of the environment variable.
Arguments after <value> are ignored. If extra arguments are
found, then an author warning is issued.
See Also
o unset() <#command:unset>
set_directory_properties
Set properties of the current directory and subdirectories.
set_directory_properties(PROPERTIES <prop1> <value1> [<prop2> <value2>] ...)
Sets properties of the current directory and its subdirectories in
key-value pairs.
See also the set_property(DIRECTORY) <#command:set_property> command.
See Properties on Directories <#directory-properties> for the list of
properties known to CMake and their individual documentation for the
behavior of each property.
See Also
o define_property() <#command:define_property>
o get_directory_property() <#command:get_directory_property>
o the more general set_property() <#command:set_property> command
set_property
Set a named property in a given scope.
set_property(<GLOBAL |
DIRECTORY [<dir>] |
TARGET [<target1> ...] |
SOURCE [<src1> ...]
[DIRECTORY <dirs> ...]
[TARGET_DIRECTORY <targets> ...] |
INSTALL [<file1> ...] |
TEST [<test1> ...]
[DIRECTORY <dir>] |
CACHE [<entry1> ...] >
[APPEND] [APPEND_STRING]
PROPERTY <name> [<value1> ...])
Sets one property on zero or more objects of a scope.
The first argument determines the scope in which the property is set.
It must be one of the following:
GLOBAL Scope is unique and does not accept a name.
DIRECTORY
Scope defaults to the current directory but other directories
(already processed by CMake) may be named by full or relative
path. Relative paths are treated as relative to the current
source directory. See also the set_directory_properties() <#
command:set_directory_properties> command.
Added in version 3.19: <dir> may reference a binary directory.
TARGET Scope may name zero or more existing targets. See also the
set_target_properties() <#command:set_target_properties>
command.
Alias Targets <#alias-targets> do not support setting target
properties.
SOURCE Scope may name zero or more source files. By default, source
file properties are only visible to targets added in the same
directory (CMakeLists.txt).
Added in version 3.18: Visibility can be set in other directory
scopes using one or both of the following sub-options:
DIRECTORY <dirs>...
The source file property will be set in each of the
<dirs> directories' scopes. CMake must already know
about each of these directories, either by having added
them through a call to add_subdirectory() <#
command:add_subdirectory> or it being the top level
source directory. Relative paths are treated as relative
to the current source directory.
Added in version 3.19: <dirs> may reference a binary
directory.
TARGET_DIRECTORY <targets>...
The source file property will be set in each of the
directory scopes where any of the specified <targets>
were created (the <targets> must therefore already
exist).
See also the set_source_files_properties() <#
command:set_source_files_properties> command.
INSTALL
Added in version 3.1.
Scope may name zero or more installed file paths. These are
made available to CPack to influence deployment.
Both the property key and value may use generator expressions.
Specific properties may apply to installed files and/or
directories.
Path components have to be separated by forward slashes, must be
normalized and are case sensitive.
To reference the installation prefix itself with a relative path
use ..
Currently installed file properties are only defined for the WIX
generator where the given paths are relative to the installation
prefix.
TEST Scope is limited to the directory the command is called in. It
may name zero or more existing tests. See also command
set_tests_properties() <#command:set_tests_properties>.
Test property values may be specified using generator
expressions <#manual:cmake-generator-expressions(7)> for tests
created by the add_test(NAME) <#command:add_test> signature.
Added in version 3.28: Visibility can be set in other directory
scopes using the following sub-option:
DIRECTORY <dir>
The test property will be set in the <dir> directory's
scope. CMake must already know about this directory,
either by having added it through a call to
add_subdirectory() <#command:add_subdirectory> or it
being the top level source directory. Relative paths are
treated as relative to the current source directory.
<dir> may reference a binary directory.
CACHE Scope must name zero or more existing cache entries.
The required PROPERTY option is immediately followed by the name of the
property to set. Remaining arguments are used to compose the property
value in the form of a semicolon-separated list.
If the APPEND option is given the list is appended to any existing
property value (except that empty values are ignored and not appended).
If the APPEND_STRING option is given the string is appended to any
existing property value as string, i.e. it results in a longer string
and not a list of strings. When using APPEND or APPEND_STRING with a
property defined to support INHERITED behavior (see define_property()
<#command:define_property>), no inheriting occurs when finding the
initial value to append to. If the property is not already directly
set in the nominated scope, the command will behave as though APPEND or
APPEND_STRING had not been given.
Note:
The GENERATED <#prop_sf:GENERATED> source file property may be
globally visible. See its documentation for details.
See Also
o define_property() <#command:define_property>
o get_property() <#command:get_property>
o The cmake-properties(7) <#manual:cmake-properties(7)> manual for a
list of properties in each scope.
site_name
Set the given variable to the name of the computer.
site_name(variable)
On UNIX-like platforms, if the variable HOSTNAME is set, its value will
be executed as a command expected to print out the host name, much like
the hostname command-line tool.
string
String operations.
Synopsis
Search and Replace
string(FIND <string> <substring> <out-var> [...])
string(REPLACE <match-string> <replace-string> <out-var> <input>...)
string(REGEX MATCH <match-regex> <out-var> <input>...)
string(REGEX MATCHALL <match-regex> <out-var> <input>...)
string(REGEX REPLACE <match-regex> <replace-expr> <out-var> <input>...)
Manipulation
string(APPEND <string-var> [<input>...])
string(PREPEND <string-var> [<input>...])
string(CONCAT <out-var> [<input>...])
string(JOIN <glue> <out-var> [<input>...])
string(TOLOWER <string> <out-var>)
string(TOUPPER <string> <out-var>)
string(LENGTH <string> <out-var>)
string(SUBSTRING <string> <begin> <length> <out-var>)
string(STRIP <string> <out-var>)
string(GENEX_STRIP <string> <out-var>)
string(REPEAT <string> <count> <out-var>)
Comparison
string(COMPARE <op> <string1> <string2> <out-var>)
Hashing
string(<HASH> <out-var> <input>)
Generation
string(ASCII <number>... <out-var>)
string(HEX <string> <out-var>)
string(CONFIGURE <string> <out-var> [...])
string(MAKE_C_IDENTIFIER <string> <out-var>)
string(RANDOM [<option>...] <out-var>)
string(TIMESTAMP <out-var> [<format string>] [UTC])
string(UUID <out-var> ...)
JSON
string(JSON <out-var> [ERROR_VARIABLE <error-var>]
{GET | TYPE | LENGTH | REMOVE}
<json-string> <member|index> [<member|index> ...])
string(JSON <out-var> [ERROR_VARIABLE <error-var>]
MEMBER <json-string>
[<member|index> ...] <index>)
string(JSON <out-var> [ERROR_VARIABLE <error-var>]
SET <json-string>
<member|index> [<member|index> ...] <value>)
string(JSON <out-var> [ERROR_VARIABLE <error-var>]
EQUAL <json-string1> <json-string2>)
Search and Replace
Search and Replace With Plain Strings
string(FIND <string> <substring> <output_variable> [REVERSE])
Return the position where the given <substring> was found in the
supplied <string>. If the REVERSE flag was used, the command
will search for the position of the last occurrence of the
specified <substring>. If the <substring> is not found, a
position of -1 is returned.
The string(FIND) subcommand treats all strings as ASCII-only
characters. The index stored in <output_variable> will also be
counted in bytes, so strings containing multi-byte characters
may lead to unexpected results.
string(REPLACE <match_string> <replace_string> <output_variable>
<input> [<input>...])
Replace all occurrences of <match_string> in the <input> with
<replace_string> and store the result in the <output_variable>.
Search and Replace With Regular Expressions
string(REGEX MATCH <regular_expression> <output_variable> <input>
[<input>...])
Match the <regular_expression> once and store the match in the
<output_variable>. All <input> arguments are concatenated
before matching. Regular expressions are specified in the
subsection just below.
string(REGEX MATCHALL <regular_expression> <output_variable> <input>
[<input>...])
Match the <regular_expression> as many times as possible and
store the matches in the <output_variable> as a list. All
<input> arguments are concatenated before matching.
string(REGEX REPLACE <regular_expression> <replacement_expression>
<output_variable> <input> [<input>...])
Match the <regular_expression> as many times as possible and
substitute the <replacement_expression> for the match in the
output. All <input> arguments are concatenated before matching.
The <replacement_expression> may refer to parenthesis-delimited
subexpressions of the match using \1, \2, ..., \9. Note that
two backslashes (\\1) are required in CMake code to get a
backslash through argument parsing.
Regex Specification
The following characters have special meaning in regular expressions:
^ Matches at beginning of input
$ Matches at end of input
. Matches any single character
\<char>
Matches the single character specified by <char>. Use this to
match special regex characters, e.g. \. for a literal . or \\
for a literal backslash \. Escaping a non-special character is
unnecessary but allowed, e.g. \a matches a.
[ ] Matches any character(s) inside the brackets. To match a
literal ], make it the first character, e.g., []ab].
[^ ] Matches any character(s) not inside the brackets. To not match
a literal ], make it the first character, e.g., [^]ab].
- Inside brackets, specifies an inclusive range between characters
on either side, e.g., [a-f] is [abcdef]. To match a literal -
using brackets, make it the first or the last character, e.g.,
[+*/-] matches basic mathematical operators.
* Matches preceding pattern zero or more times
+ Matches preceding pattern one or more times
? Matches preceding pattern zero or once only
| Matches a pattern on either side of the |
() Saves a matched subexpression, which can be referenced in the
REGEX REPLACE operation.
Added in version 3.9: All regular expression-related commands,
including e.g. if(MATCHES) <#matches>, save subgroup matches in
the variables CMAKE_MATCH_<n> <#variable:CMAKE_MATCH_<n>> for
<n> 0..9.
*, + and ? have higher precedence than concatenation. | has lower
precedence than concatenation. This means that the regular expression
^ab+d$ matches abbd but not ababd, and the regular expression ^(ab|cd)$
matches ab but not abd.
CMake language Escape Sequences <#escape-sequences> such as \t, \r, \n,
and \\ may be used to construct literal tabs, carriage returns,
newlines, and backslashes (respectively) to pass in a regex. For
example:
o The quoted argument "[ \t\r\n]" specifies a regex that matches any
single whitespace character.
o The quoted argument "[/\\]" specifies a regex that matches a single
forward slash / or backslash \.
o The quoted argument "[A-Za-z0-9_]" specifies a regex that matches any
single "word" character in the C locale.
o The quoted argument "\\(\\a\\+b\\)" specifies a regex that matches
the exact string (a+b). Each \\ is parsed in a quoted argument as
just \, so the regex itself is actually \(\a\+\b\). This can
alternatively be specified in a Bracket Argument <#bracket-argument>
without having to escape the backslashes, e.g. [[\(\a\+\b\)]].
Manipulation
string(APPEND <string_variable> [<input>...])
Added in version 3.4.
Append all the <input> arguments to the string.
string(PREPEND <string_variable> [<input>...])
Added in version 3.10.
Prepend all the <input> arguments to the string.
string(CONCAT <output_variable> [<input>...])
Concatenate all the <input> arguments together and store the
result in the named <output_variable>.
string(JOIN <glue> <output_variable> [<input>...])
Added in version 3.12.
Join all the <input> arguments together using the <glue> string
and store the result in the named <output_variable>.
To join a list's elements, prefer to use the JOIN operator from
the list() <#command:list> command. This allows for the
elements to have special characters like ; in them.
string(TOLOWER <string> <output_variable>)
Convert <string> to lower characters.
string(TOUPPER <string> <output_variable>)
Convert <string> to upper characters.
string(LENGTH <string> <output_variable>)
Store in an <output_variable> a given string's length in bytes.
Note that this means if <string> contains multi-byte characters,
the result stored in <output_variable> will not be the number of
characters.
string(SUBSTRING <string> <begin> <length> <output_variable>)
Store in an <output_variable> a substring of a given <string>.
If <length> is -1 the remainder of the string starting at
<begin> will be returned.
Changed in version 3.2: If <string> is shorter than <length>
then the end of the string is used instead. Previous versions
of CMake reported an error in this case.
Both <begin> and <length> are counted in bytes, so care must be
exercised if <string> could contain multi-byte characters.
string(STRIP <string> <output_variable>)
Store in an <output_variable> a substring of a given <string>
with leading and trailing spaces removed.
string(GENEX_STRIP <string> <output_variable>)
Added in version 3.1.
Strip any generator expressions <#manual:cmake-generator-
expressions(7)> from the input <string> and store the result in
the <output_variable>.
string(REPEAT <string> <count> <output_variable>)
Added in version 3.15.
Produce the output string as the input <string> repeated <count>
times.
Comparison
string(COMPARE LESS <string1> <string2> <output_variable>)
string(COMPARE GREATER <string1> <string2> <output_variable>)
string(COMPARE EQUAL <string1> <string2> <output_variable>)
string(COMPARE NOTEQUAL <string1> <string2> <output_variable>)
string(COMPARE LESS_EQUAL <string1> <string2> <output_variable>)
string(COMPARE GREATER_EQUAL <string1> <string2> <output_variable>)
Compare the strings and store true or false in the
<output_variable>.
Added in version 3.7: Added the LESS_EQUAL and GREATER_EQUAL
options.
Hashing
string(<HASH> <output_variable> <input>)
Compute a cryptographic hash of the <input> string. The
supported <HASH> algorithm names are:
MD5 Message-Digest Algorithm 5, RFC 1321.
SHA1 US Secure Hash Algorithm 1, RFC 3174.
SHA224 US Secure Hash Algorithms, RFC 4634.
SHA256 US Secure Hash Algorithms, RFC 4634.
SHA384 US Secure Hash Algorithms, RFC 4634.
SHA512 US Secure Hash Algorithms, RFC 4634.
SHA3_224
Keccak SHA-3.
SHA3_256
Keccak SHA-3.
SHA3_384
Keccak SHA-3.
SHA3_512
Keccak SHA-3.
Added in version 3.8: Added the SHA3_* hash algorithms.
Generation
string(ASCII <number> [<number> ...] <output_variable>)
Convert all numbers into corresponding ASCII characters.
string(HEX <string> <output_variable>)
Added in version 3.18.
Convert each byte in the input <string> to its hexadecimal
representation and store the concatenated hex digits in the
<output_variable>. Letters in the output (a through f) are in
lowercase.
string(CONFIGURE <string> <output_variable> [@ONLY] [ESCAPE_QUOTES])
Transform a <string> like configure_file() <#
command:configure_file> transforms a file.
string(MAKE_C_IDENTIFIER <string> <output_variable>)
Convert each non-alphanumeric character in the input <string> to
an underscore and store the result in the <output_variable>. If
the first character of the <string> is a digit, an underscore
will also be prepended to the result.
string(RANDOM [LENGTH <length>] [ALPHABET <alphabet>]
[RANDOM_SEED <seed>] <output_variable>)
Return a random string of given <length> consisting of
characters from the given <alphabet>. Default length is 5
characters and default alphabet is all numbers and upper and
lower case letters. If an integer RANDOM_SEED is given, its
value will be used to seed the random number generator.
string(TIMESTAMP <output_variable> [<format_string>] [UTC])
Write a string representation of the current date and/or time to
the <output_variable>.
If the command is unable to obtain a timestamp, the
<output_variable> will be set to the empty string "".
The optional UTC flag requests the current date/time
representation to be in Coordinated Universal Time (UTC) rather
than local time.
The optional <format_string> may contain the following format
specifiers:
%% Added in version 3.8.
A literal percent sign (%).
%d The day of the current month (01-31).
%H The hour on a 24-hour clock (00-23).
%I The hour on a 12-hour clock (01-12).
%j The day of the current year (001-366).
%m The month of the current year (01-12).
%b Added in version 3.7.
Abbreviated month name (e.g. Oct).
%B Added in version 3.10.
Full month name (e.g. October).
%M The minute of the current hour (00-59).
%s Added in version 3.6.
Seconds since midnight (UTC) 1-Jan-1970 (UNIX time).
%S The second of the current minute. 60 represents a leap
second. (00-60)
%f Added in version 3.23.
The microsecond of the current second (000000-999999).
%U The week number of the current year (00-53).
%V Added in version 3.22.
The ISO 8601 week number of the current year (01-53).
%w The day of the current week. 0 is Sunday. (0-6)
%a Added in version 3.7.
Abbreviated weekday name (e.g. Fri).
%A Added in version 3.10.
Full weekday name (e.g. Friday).
%y The last two digits of the current year (00-99).
%Y The current year.
%z Added in version 3.26.
The offset of the time zone from UTC, in hours and
minutes, with format +hhmm or -hhmm.
%Z Added in version 3.26.
The time zone name.
Unknown format specifiers will be ignored and copied to the
output as-is.
If no explicit <format_string> is given, it will default to:
%Y-%m-%dT%H:%M:%S for local time.
%Y-%m-%dT%H:%M:%SZ for UTC.
Added in version 3.8: If the SOURCE_DATE_EPOCH environment
variable is set, its value will be used instead of the current
time. See <https://reproducible-builds.org/specs/source-date-
epoch/> for details.
string(UUID <output_variable> NAMESPACE <namespace> NAME <name> TYPE
<MD5|SHA1> [UPPER])
Added in version 3.1.
Create a universally unique identifier (aka GUID) as per RFC4122
based on the hash of the combined values of <namespace> (which
itself has to be a valid UUID) and <name>. The hash algorithm
can be either MD5 (Version 3 UUID) or SHA1 (Version 5 UUID). A
UUID has the format xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx where
each x represents a lower case hexadecimal character. Where
required, an uppercase representation can be requested with the
optional UPPER flag.
JSON
Added in version 3.19.
Functionality for querying a JSON string.
Note:
In each of the following JSON-related subcommands, if the optional
ERROR_VARIABLE argument is given, errors will be reported in
<error-variable> and the <out-var> will be set to
<member|index>-[<member|index>...]-NOTFOUND with the path elements
up to the point where the error occurred, or just NOTFOUND if there
is no relevant path. If an error occurs but the ERROR_VARIABLE
option is not present, a fatal error message is generated. If no
error occurs, the <error-variable> will be set to NOTFOUND.
string(JSON <out-var> [ERROR_VARIABLE <error-variable>] GET
<json-string> <member|index> [<member|index> ...])
Get an element from <json-string> at the location given by the
list of <member|index> arguments. Array and object elements
will be returned as a JSON string. Boolean elements will be
returned as ON or OFF. Null elements will be returned as an
empty string. Number and string types will be returned as
strings.
string(JSON <out-var> [ERROR_VARIABLE <error-variable>] TYPE
<json-string> <member|index> [<member|index> ...])
Get the type of an element in <json-string> at the location
given by the list of <member|index> arguments. The <out-var>
will be set to one of NULL, NUMBER, STRING, BOOLEAN, ARRAY, or
OBJECT.
string(JSON <out-var> [ERROR_VARIABLE <error-var>] MEMBER <json-string>
[<member|index> ...] <index>)
Get the name of the <index>-th member in <json-string> at the
location given by the list of <member|index> arguments.
Requires an element of object type.
string(JSON <out-var> [ERROR_VARIABLE <error-variable>] LENGTH
<json-string> [<member|index> ...])
Get the length of an element in <json-string> at the location
given by the list of <member|index> arguments. Requires an
element of array or object type.
string(JSON <out-var> [ERROR_VARIABLE <error-variable>] REMOVE
<json-string> <member|index> [<member|index> ...])
Remove an element from <json-string> at the location given by
the list of <member|index> arguments. The JSON string without
the removed element will be stored in <out-var>.
string(JSON <out-var> [ERROR_VARIABLE <error-variable>] SET
<json-string> <member|index> [<member|index> ...] <value>)
Set an element in <json-string> at the location given by the
list of <member|index> arguments to <value>. The contents of
<value> should be valid JSON. If <json-string> is an array,
<value> can be appended to the end of the array by using a
number greater or equal to the array length as the
<member|index> argument.
string(JSON <out-var> [ERROR_VARIABLE <error-var>] EQUAL <json-string1>
<json-string2>)
Compare the two JSON objects given by <json-string1> and
<json-string2> for equality. The contents of <json-string1> and
<json-string2> should be valid JSON. The <out-var> will be set
to a true value if the JSON objects are considered equal, or a
false value otherwise.
unset
Unset a variable, cache variable, or environment variable.
Unset Normal Variable or Cache Entry
unset(<variable> [CACHE | PARENT_SCOPE])
Removes a normal variable from the current scope, causing it to become
undefined. If CACHE is present, then a cache variable is removed
instead of a normal variable.
If PARENT_SCOPE is present then the variable is removed from the scope
above the current scope. See the same option in the set() <#
command:set> command for further details.
Note:
When evaluating Variable References <#variable-references> of the
form ${VAR}, CMake first searches for a normal variable with that
name. If no such normal variable exists, CMake will then search for
a cache entry with that name. Because of this, unsetting a normal
variable can expose a cache variable that was previously hidden. To
force a variable reference of the form ${VAR} to return an empty
string, use set(<variable> ""), which clears the normal variable but
leaves it defined.
Unset Environment Variable
unset(ENV{<variable>})
Removes <variable> from the currently available Environment Variables
<#manual:cmake-env-variables(7)>. Subsequent calls of $ENV{<variable>}
will return the empty string.
This command affects only the current CMake process, not the process
from which CMake was called, nor the system environment at large, nor
the environment of subsequent build or test processes.
See Also
o set() <#command:set>
variable_watch
Watch the CMake variable for change.
variable_watch(<variable> [<command>])
If the specified <variable> changes and no <command> is given, a
message will be printed to inform about the change.
If <command> is given, this command will be executed instead. The
command will receive the following arguments: COMMAND(<variable>
<access> <value> <current_list_file> <stack>)
<variable>
Name of the variable being accessed.
<access>
One of READ_ACCESS, UNKNOWN_READ_ACCESS, MODIFIED_ACCESS,
UNKNOWN_MODIFIED_ACCESS, or REMOVED_ACCESS. The UNKNOWN_ values
are only used when the variable has never been set. Once set,
they are never used again during the same CMake run, even if the
variable is later unset.
<value>
The value of the variable. On a modification, this is the new
(modified) value of the variable. On removal, the value is
empty.
<current_list_file>
Full path to the file doing the access.
<stack>
List of absolute paths of all files currently on the stack of
file inclusion, with the bottom-most file first and the
currently processed file (that is, current_list_file) last.
Note that for some accesses such as list(APPEND) <#append>, the watcher
is executed twice, first with a read access and then with a write one.
Also note that an if(DEFINED) <#defined> query on the variable does not
register as an access and the watcher is not executed.
Only non-cache variables can be watched using this command. Access to
cache variables is never watched. However, the existence of a cache
variable var causes accesses to the non-cache variable var to not use
the UNKNOWN_ prefix, even if a non-cache variable var has never
existed.
while
Evaluate a group of commands while a condition is true
while(<condition>)
<commands>
endwhile()
All commands between while and the matching endwhile() <#
command:endwhile> are recorded without being invoked. Once the
endwhile() <#command:endwhile> is evaluated, the recorded list of
commands is invoked as long as the <condition> is true.
The <condition> has the same syntax and is evaluated using the same
logic as described at length for the if() <#command:if> command.
The commands break() <#command:break> and continue() <#
command:continue> provide means to escape from the normal control flow.
Per legacy, the endwhile() <#command:endwhile> command admits an
optional <condition> argument. If used, it must be a verbatim repeat
of the argument of the opening while command.
See Also
o break() <#command:break>
o continue() <#command:continue>
o foreach() <#command:foreach>
o endwhile() <#command:endwhile>
PROJECT COMMANDS
These commands are available only in CMake projects.
add_compile_definitions
Added in version 3.12.
Add preprocessor definitions to the compilation of source files.
add_compile_definitions(<definition> ...)
Adds preprocessor definitions to the compiler command line.
The preprocessor definitions are added to the COMPILE_DEFINITIONS <#
prop_dir:COMPILE_DEFINITIONS> directory property for the current
CMakeLists file. They are also added to the COMPILE_DEFINITIONS <#
prop_tgt:COMPILE_DEFINITIONS> target property for each target in the
current CMakeLists file.
Definitions are specified using the syntax VAR or VAR=value.
Function-style definitions are not supported. CMake will automatically
escape the value correctly for the native build system (note that CMake
language syntax may require escapes to specify some values).
Added in version 3.26: Any leading -D on an item will be removed.
Arguments to add_compile_definitions may use generator expressions with
the syntax $<...>. See the cmake-generator-expressions(7) <#
manual:cmake-generator-expressions(7)> manual for available
expressions. See the cmake-buildsystem(7) <#manual:cmake-
buildsystem(7)> manual for more on defining buildsystem properties.
See Also
o The command target_compile_definitions() <#
command:target_compile_definitions> adds target-specific definitions.
add_compile_options
Add options to the compilation of source files.
add_compile_options(<option> ...)
Adds options to the COMPILE_OPTIONS <#prop_dir:COMPILE_OPTIONS>
directory property. These options are used when compiling targets from
the current directory and below.
Note:
These options are not used when linking. See the add_link_options()
<#command:add_link_options> command for that.
Arguments
Arguments to add_compile_options may use generator expressions with the
syntax $<...>. See the cmake-generator-expressions(7) <#manual:cmake-
generator-expressions(7)> manual for available expressions. See the
cmake-buildsystem(7) <#manual:cmake-buildsystem(7)> manual for more on
defining buildsystem properties.
Option De-duplication
The final set of options used for a target is constructed by
accumulating options from the current target and the usage requirements
of its dependencies. The set of options is de-duplicated to avoid
repetition.
Added in version 3.12: While beneficial for individual options, the
de-duplication step can break up option groups. For example, -option A
-option B becomes -option A B. One may specify a group of options
using shell-like quoting along with a SHELL: prefix. The SHELL: prefix
is dropped, and the rest of the option string is parsed using the
separate_arguments() <#command:separate_arguments> UNIX_COMMAND mode.
For example, "SHELL:-option A" "SHELL:-option B" becomes -option A
-option B.
Example
Since different compilers support different options, a typical use of
this command is in a compiler-specific conditional clause:
if (MSVC)
# warning level 4
add_compile_options(/W4)
else()
# additional warnings
add_compile_options(-Wall -Wextra -Wpedantic)
endif()
To set per-language options, use the $<COMPILE_LANGUAGE> <#
genex:COMPILE_LANGUAGE> or $<COMPILE_LANGUAGE:languages> <#
genex:COMPILE_LANGUAGE> generator expressions.
See Also
o This command can be used to add any options. However, for adding
preprocessor definitions and include directories it is recommended to
use the more specific commands add_compile_definitions() <#
command:add_compile_definitions> and include_directories() <#
command:include_directories>.
o The command target_compile_options() <#
command:target_compile_options> adds target-specific options.
o This command adds compile options for all languages. Use the
COMPILE_LANGUAGE <#genex:COMPILE_LANGUAGE> generator expression to
specify per-language compile options.
o The source file property COMPILE_OPTIONS <#prop_sf:COMPILE_OPTIONS>
adds options to one source file.
o add_link_options() <#command:add_link_options> adds options for
linking.
o CMAKE_<LANG>_FLAGS <#variable:CMAKE_<LANG>_FLAGS> and
CMAKE_<LANG>_FLAGS_<CONFIG> <#variable:CMAKE_<LANG>_FLAGS_<CONFIG>>
add language-wide flags passed to all invocations of the compiler.
This includes invocations that drive compiling and those that drive
linking.
add_custom_command
Add a custom build rule to the generated build system.
There are two main signatures for add_custom_command.
Generating Files
The first signature is for adding a custom command to produce an
output:
add_custom_command(OUTPUT output1 [output2 ...]
COMMAND command1 [ARGS] [args1...]
[COMMAND command2 [ARGS] [args2...] ...]
[MAIN_DEPENDENCY depend]
[DEPENDS [depends...]]
[BYPRODUCTS [files...]]
[IMPLICIT_DEPENDS <lang1> depend1
[<lang2> depend2] ...]
[WORKING_DIRECTORY dir]
[COMMENT comment]
[DEPFILE depfile]
[JOB_POOL job_pool]
[JOB_SERVER_AWARE <bool>]
[VERBATIM] [APPEND] [USES_TERMINAL]
[CODEGEN]
[COMMAND_EXPAND_LISTS]
[DEPENDS_EXPLICIT_ONLY])
This defines a command to generate specified OUTPUT file(s). A target
created in the same directory (CMakeLists.txt file) that specifies any
output of the custom command as a source file is given a rule to
generate the file using the command at build time.
Do not list the output in more than one independent target that may
build in parallel or the instances of the rule may conflict. Instead,
use the add_custom_target() <#command:add_custom_target> command to
drive the command and make the other targets depend on that one. See
the Example: Generating Files for Multiple Targets below.
The options are:
APPEND Append the COMMAND and DEPENDS option values to the custom
command for the first output specified. There must have already
been a previous call to this command with the same output.
If the previous call specified the output via a generator
expression, the output specified by the current call must match
in at least one configuration after evaluating generator
expressions. In this case, the appended commands and
dependencies apply to all configurations.
The COMMENT, MAIN_DEPENDENCY, and WORKING_DIRECTORY options are
currently ignored when APPEND is given, but may be used in the
future.
BYPRODUCTS
Added in version 3.2.
Specify the files the command is expected to produce but whose
modification time may or may not be newer than the dependencies.
If a byproduct name is a relative path it will be interpreted
relative to the build tree directory corresponding to the
current source directory. Each byproduct file will be marked
with the GENERATED <#prop_sf:GENERATED> source file property
automatically.
See policy CMP0058 <#policy:CMP0058> for the motivation behind
this feature.
Explicit specification of byproducts is supported by the Ninja
<#generator:Ninja> generator to tell the ninja build tool how to
regenerate byproducts when they are missing. It is also useful
when other build rules (e.g. custom commands) depend on the
byproducts. Ninja requires a build rule for any generated file
on which another rule depends even if there are order-only
dependencies to ensure the byproducts will be available before
their dependents build.
The Makefile Generators <#makefile-generators> will remove
BYPRODUCTS and other GENERATED <#prop_sf:GENERATED> files during
make clean.
This keyword cannot be used with APPEND (see policy CMP0175 <#
policy:CMP0175>). All byproducts must be set in the first call
to add_custom_command(OUTPUT...) for the output files.
Added in version 3.20: Arguments to BYPRODUCTS may use a
restricted set of generator expressions <#manual:cmake-
generator-expressions(7)>. Target-dependent expressions <#
target-dependent-expressions> are not permitted.
Changed in version 3.28: In targets using File Sets <#file-
sets>, custom command byproducts are now considered private
unless they are listed in a non-private file set. See policy
CMP0154 <#policy:CMP0154>.
COMMAND
Specify the command-line(s) to execute at build time. At least
one COMMAND would normally be given, but certain patterns may
omit it, such as adding commands in separate calls using APPEND.
If more than one COMMAND is specified, they will be executed in
order, but not necessarily composed into a stateful shell or
batch script. To run a full script, use the configure_file() <#
command:configure_file> command or the file(GENERATE) <#
generate> command to create it, and then specify a COMMAND to
launch it.
The optional ARGS argument is for backward compatibility and
will be ignored.
If COMMAND specifies an executable target name (created by the
add_executable() <#command:add_executable> command), it will
automatically be replaced by the location of the executable
created at build time if either of the following is true:
o The target is not being cross-compiled (i.e. the
CMAKE_CROSSCOMPILING <#variable:CMAKE_CROSSCOMPILING> variable
is not set to true).
o Added in version 3.6: The target is being cross-compiled and
an emulator is provided (i.e. its CROSSCOMPILING_EMULATOR <#
prop_tgt:CROSSCOMPILING_EMULATOR> target property is set). In
this case, the contents of CROSSCOMPILING_EMULATOR <#
prop_tgt:CROSSCOMPILING_EMULATOR> will be prepended to the
command before the location of the target executable.
If neither of the above conditions are met, it is assumed that
the command name is a program to be found on the PATH at build
time.
Arguments to COMMAND may use generator expressions <#
manual:cmake-generator-expressions(7)>. Use the TARGET_FILE <#
genex:TARGET_FILE> generator expression to refer to the location
of a target later in the command line (i.e. as a command
argument rather than as the command to execute).
Whenever one of the following target based generator expressions
are used as a command to execute or is mentioned in a command
argument, a target-level dependency will be added automatically
so that the mentioned target will be built before any target
using this custom command (see policy CMP0112 <#
policy:CMP0112>).
o TARGET_FILE
o TARGET_LINKER_FILE
o TARGET_SONAME_FILE
o TARGET_PDB_FILE
This target-level dependency does NOT add a file-level
dependency that would cause the custom command to re-run
whenever the executable is recompiled. List target names with
the DEPENDS option to add such file-level dependencies.
COMMENT
Display the given message before the commands are executed at
build time. This will be ignored if APPEND is given, although a
future version may use it.
Added in version 3.26: Arguments to COMMENT may use generator
expressions <#manual:cmake-generator-expressions(7)>.
DEPENDS
Specify files on which the command depends. Each argument is
converted to a dependency as follows:
1. If the argument is the name of a target (created by the
add_custom_target() <#command:add_custom_target>,
add_executable() <#command:add_executable>, or add_library()
<#command:add_library> command) a target-level dependency is
created to make sure the target is built before any target
using this custom command. Additionally, if the target is an
executable or library, a file-level dependency is created to
cause the custom command to re-run whenever the target is
recompiled.
2. If the argument is an absolute path, a file-level dependency
is created on that path.
3. If the argument is the name of a source file that has been
added to a target or on which a source file property has been
set, a file-level dependency is created on that source file.
4. If the argument is a relative path and it exists in the
current source directory, a file-level dependency is created
on that file in the current source directory.
5. Otherwise, a file-level dependency is created on that path
relative to the current binary directory.
If any dependency is an OUTPUT of another custom command in the
same directory (CMakeLists.txt file), CMake automatically brings
the other custom command into the target in which this command
is built.
Added in version 3.16: A target-level dependency is added if any
dependency is listed as BYPRODUCTS of a target or any of its
build events in the same directory to ensure the byproducts will
be available.
If DEPENDS is not specified, the command will run whenever the
OUTPUT is missing; if the command does not actually create the
OUTPUT, the rule will always run.
Added in version 3.1: Arguments to DEPENDS may use generator
expressions <#manual:cmake-generator-expressions(7)>.
COMMAND_EXPAND_LISTS
Added in version 3.8.
Lists in COMMAND arguments will be expanded, including those
created with generator expressions <#manual:cmake-generator-
expressions(7)>, allowing COMMAND arguments such as ${CC}
"-I$<JOIN:$<TARGET_PROPERTY:foo,INCLUDE_DIRECTORIES>,;-I>"
foo.cc to be properly expanded.
This keyword cannot be used with APPEND (see policy CMP0175 <#
policy:CMP0175>). If the appended commands need this option to
be set, it must be set on the first call to
add_custom_command(OUTPUT...) for the output files.
CODEGEN
Added in version 3.31.
Adds the custom command to a global codegen target that can be
used to execute the custom command while avoiding the majority
of the build graph.
This option is supported only by Ninja Generators <#ninja-
generators> and Makefile Generators <#makefile-generators>, and
is ignored by other generators. Furthermore, this option is
allowed only if policy CMP0171 <#policy:CMP0171> is set to NEW.
This keyword cannot be used with APPEND (see policy CMP0175 <#
policy:CMP0175>). It can only be set on the first call to
add_custom_command(OUTPUT...) for the output files.
IMPLICIT_DEPENDS
Request scanning of implicit dependencies of an input file. The
language given specifies the programming language whose
corresponding dependency scanner should be used. Currently only
C and CXX language scanners are supported. The language has to
be specified for every file in the IMPLICIT_DEPENDS list.
Dependencies discovered from the scanning are added to those of
the custom command at build time. Note that the
IMPLICIT_DEPENDS option is currently supported only for Makefile
generators and will be ignored by other generators.
Note:
This option cannot be specified at the same time as DEPFILE
option.
JOB_POOL
Added in version 3.15.
Specify a pool <#prop_gbl:JOB_POOLS> for the Ninja <#
generator:Ninja> generator. Incompatible with USES_TERMINAL,
which implies the console pool. Using a pool that is not
defined by JOB_POOLS <#prop_gbl:JOB_POOLS> causes an error by
ninja at build time.
This keyword cannot be used with APPEND (see policy CMP0175 <#
policy:CMP0175>). Job pools can only be specified in the first
call to add_custom_command(OUTPUT...) for the output files.
JOB_SERVER_AWARE
Added in version 3.28.
Specify that the command is GNU Make job server aware.
For the Unix Makefiles <#generator:Unix Makefiles>, MSYS
Makefiles <#generator:MSYS Makefiles>, and MinGW Makefiles <#
generator:MinGW Makefiles> generators this will add the + prefix
to the recipe line. See the GNU Make Documentation <https://www
.gnu.org/software/make/manual/html_node/MAKE-Variable.html> for
more information.
This option is silently ignored by other generators.
This keyword cannot be used with APPEND (see policy CMP0175 <#
policy:CMP0175>). Job server awareness can only be specified in
the first call to add_custom_command(OUTPUT...) for the output
files.
MAIN_DEPENDENCY
Specify the primary input source file to the command. This is
treated just like any value given to the DEPENDS option but also
suggests to Visual Studio generators where to hang the custom
command. Each source file may have at most one command
specifying it as its main dependency. A compile command (i.e.
for a library or an executable) counts as an implicit main
dependency which gets silently overwritten by a custom command
specification.
This option is currently ignored if APPEND is given, but a
future version may use it.
OUTPUT Specify the output files the command is expected to produce.
Each output file will be marked with the GENERATED <#
prop_sf:GENERATED> source file property automatically. If the
output of the custom command is not actually created as a file
on disk it should be marked with the SYMBOLIC <#
prop_sf:SYMBOLIC> source file property.
If an output file name is a relative path, its absolute path is
determined by interpreting it relative to:
1. the build directory corresponding to the current source
directory (CMAKE_CURRENT_BINARY_DIR <#
variable:CMAKE_CURRENT_BINARY_DIR>), or
2. the current source directory (CMAKE_CURRENT_SOURCE_DIR <#
variable:CMAKE_CURRENT_SOURCE_DIR>).
The path in the build directory is preferred unless the path in
the source tree is mentioned as an absolute source file path
elsewhere in the current directory.
The output file path may not contain < or > characters.
Added in version 3.20: Arguments to OUTPUT may use a restricted
set of generator expressions <#manual:cmake-generator-
expressions(7)>. Target-dependent expressions <#target-
dependent-expressions> are not permitted.
Changed in version 3.28: In targets using File Sets <#file-
sets>, custom command outputs are now considered private unless
they are listed in a non-private file set. See policy CMP0154
<#policy:CMP0154>.
Changed in version 3.30: The output file path may now use #
characters, except when using the Borland Makefiles <#
generator:Borland Makefiles> generator.
USES_TERMINAL
Added in version 3.2.
The command will be given direct access to the terminal if
possible. With the Ninja <#generator:Ninja> generator, this
places the command in the console pool <#prop_gbl:JOB_POOLS>.
This keyword cannot be used with APPEND (see policy CMP0175 <#
policy:CMP0175>). If the appended commands need access to the
terminal, it must be set on the first call to
add_custom_command(OUTPUT...) for the output files.
VERBATIM
All arguments to the commands will be escaped properly for the
build tool so that the invoked command receives each argument
unchanged. Note that one level of escapes is still used by the
CMake language processor before add_custom_command even sees the
arguments. Use of VERBATIM is recommended as it enables correct
behavior. When VERBATIM is not given the behavior is platform
specific because there is no protection of tool-specific special
characters.
This keyword cannot be used with APPEND (see policy CMP0175 <#
policy:CMP0175>). If the appended commands need to be treated
as VERBATIM, it must be set on the first call to
add_custom_command(OUTPUT...) for the output files.
WORKING_DIRECTORY
Execute the command with the given current working directory.
If it is a relative path, it will be interpreted relative to the
build tree directory corresponding to the current source
directory.
This option is currently ignored if APPEND is given, but a
future version may use it.
Added in version 3.13: Arguments to WORKING_DIRECTORY may use
generator expressions <#manual:cmake-generator-expressions(7)>.
DEPFILE
Added in version 3.7.
Specify a depfile which holds dependencies for the custom
command. It is usually emitted by the custom command itself.
This keyword may only be used if the generator supports it, as
detailed below.
The expected format, compatible with what is generated by gcc
with the option -M, is independent of the generator or platform.
The formal syntax, as specified using BNF <https://en.wikipedia
.org/wiki/Backus%E2%80%93Naur_form> notation with the regular
extensions, is the following:
depfile ::= rule <#grammar-token-depfile-rule>*
rule ::= targets <#grammar-token-depfile-targets> (':' (separator <#grammar-token-depfile-separator> dependencies <#grammar-token-depfile-dependencies>?)?)? eol <#grammar-token-depfile-eol>
targets ::= target <#grammar-token-depfile-target> (separator <#grammar-token-depfile-separator> target <#grammar-token-depfile-target>)* separator <#grammar-token-depfile-separator>*
target ::= pathname <#grammar-token-depfile-pathname>
dependencies ::= dependency <#grammar-token-depfile-dependency> (separator <#grammar-token-depfile-separator> dependency <#grammar-token-depfile-dependency>)* separator <#grammar-token-depfile-separator>*
dependency ::= pathname <#grammar-token-depfile-pathname>
separator ::= (space <#grammar-token-depfile-space> | line_continue <#grammar-token-depfile-line_continue>)+
line_continue ::= '\' eol <#grammar-token-depfile-eol>
space ::= ' ' | '\t'
pathname ::= character <#grammar-token-depfile-character>+
character ::= std_character <#grammar-token-depfile-std_character> | dollar <#grammar-token-depfile-dollar> | hash <#grammar-token-depfile-hash> | whitespace <#grammar-token-depfile-whitespace>
std_character ::= <any character except '$', '#' or ' '>
dollar ::= '$$'
hash ::= '\#'
whitespace ::= '\ '
eol ::= '\r'? '\n'
Note:
As part of pathname, any slash and backslash is interpreted
as a directory separator.
Added in version 3.7: The Ninja <#generator:Ninja> generator
supports DEPFILE since the keyword was first added.
Added in version 3.17: Added the Ninja Multi-Config <#
generator:Ninja Multi-Config> generator, which included support
for the DEPFILE keyword.
Added in version 3.20: Added support for Makefile Generators <#
makefile-generators>.
Note:
DEPFILE cannot be specified at the same time as the
IMPLICIT_DEPENDS option for Makefile Generators <#makefile-
generators>.
Added in version 3.21: Added support for Visual Studio
Generators <#visual-studio-generators> with VS 2012 and above,
and for the Xcode <#generator:Xcode> generator. Support for
generator expressions <#manual:cmake-generator-expressions(7)>
was also added.
Added in version 3.29: The Ninja Generators <#ninja-generators>
will now incorporate the dependencies into its "deps log"
database if the file is not listed in OUTPUTS or BYPRODUCTS.
Using DEPFILE with generators other than those listed above is
an error.
If the DEPFILE argument is relative, it should be relative to
CMAKE_CURRENT_BINARY_DIR <#variable:CMAKE_CURRENT_BINARY_DIR>,
and any relative paths inside the DEPFILE should also be
relative to CMAKE_CURRENT_BINARY_DIR <#
variable:CMAKE_CURRENT_BINARY_DIR>. See policy CMP0116 <#
policy:CMP0116>, which is always NEW for Makefile Generators <#
makefile-generators>, Visual Studio Generators <#visual-studio-
generators>, and the Xcode <#generator:Xcode> generator.
This keyword cannot be used with APPEND (see policy CMP0175 <#
policy:CMP0175>). Depfiles can only be set on the first call to
add_custom_command(OUTPUT...) for the output files.
DEPENDS_EXPLICIT_ONLY
Added in version 3.27.
Indicates that the command's DEPENDS argument represents all files
required by the command and implicit dependencies are not required.
Without this option, if any target uses the output of the custom
command, CMake will consider that target's dependencies as implicit
dependencies for the custom command in case this custom command
requires files implicitly created by those targets.
This option can be enabled on all custom commands by setting
CMAKE_ADD_CUSTOM_COMMAND_DEPENDS_EXPLICIT_ONLY <#
variable:CMAKE_ADD_CUSTOM_COMMAND_DEPENDS_EXPLICIT_ONLY> to ON.
This keyword cannot be used with APPEND (see policy CMP0175 <#
policy:CMP0175>). It can only be set on the first call to
add_custom_command(OUTPUT...) for the output files.
Only the Ninja Generators <#ninja-generators> actually use this
information to remove unnecessary implicit dependencies.
See also the OPTIMIZE_DEPENDENCIES <#prop_tgt:OPTIMIZE_DEPENDENCIES>
target property, which may provide another way for reducing the
impact of target dependencies in some scenarios.
Examples: Generating Files
Custom commands may be used to generate source files. For example, the
code:
add_custom_command(
OUTPUT out.c
COMMAND someTool -i ${CMAKE_CURRENT_SOURCE_DIR}/in.txt
-o out.c
DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/in.txt
VERBATIM)
add_library(myLib out.c)
adds a custom command to run someTool to generate out.c and then
compile the generated source as part of a library. The generation rule
will re-run whenever in.txt changes.
Added in version 3.20: One may use generator expressions to specify
per-configuration outputs. For example, the code:
add_custom_command(
OUTPUT "out-$<CONFIG>.c"
COMMAND someTool -i ${CMAKE_CURRENT_SOURCE_DIR}/in.txt
-o "out-$<CONFIG>.c"
-c "$<CONFIG>"
DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/in.txt
VERBATIM)
add_library(myLib "out-$<CONFIG>.c")
adds a custom command to run someTool to generate out-<config>.c, where
<config> is the build configuration, and then compile the generated
source as part of a library.
Added in version 3.31: Use the CODEGEN option to add a custom command's
outputs to the builtin codegen target. This is useful to make
generated code available for
static analysis without building the entire project. For example:
add_executable(someTool someTool.c)
add_custom_command(
OUTPUT out.c
COMMAND someTool -o out.c
CODEGEN)
add_library(myLib out.c)
A user may build the codegen target to generate out.c. someTool is
built as dependency, but myLib is not built at all.
Example: Generating Files for Multiple Targets
If multiple independent targets need the same custom command output, it
must be attached to a single custom target on which they all depend.
Consider the following example:
add_custom_command(
OUTPUT table.csv
COMMAND makeTable -i ${CMAKE_CURRENT_SOURCE_DIR}/input.dat
-o table.csv
DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/input.dat
VERBATIM)
add_custom_target(generate_table_csv DEPENDS table.csv)
add_custom_command(
OUTPUT foo.cxx
COMMAND genFromTable -i table.csv -case foo -o foo.cxx
DEPENDS table.csv # file-level dependency
generate_table_csv # target-level dependency
VERBATIM)
add_library(foo foo.cxx)
add_custom_command(
OUTPUT bar.cxx
COMMAND genFromTable -i table.csv -case bar -o bar.cxx
DEPENDS table.csv # file-level dependency
generate_table_csv # target-level dependency
VERBATIM)
add_library(bar bar.cxx)
Output foo.cxx is needed only by target foo and output bar.cxx is
needed only by target bar, but both targets need table.csv,
transitively. Since foo and bar are independent targets that may build
concurrently, we prevent them from racing to generate table.csv by
placing its custom command in a separate target, generate_table_csv.
The custom commands generating foo.cxx and bar.cxx each specify a
target-level dependency on generate_table_csv, so the targets using
them, foo and bar, will not build until after target generate_table_csv
is built.
Build Events
The second signature adds a custom command to a target such as a
library or executable. This is useful for performing an operation
before or after building the target. The command becomes part of the
target and will only execute when the target itself is built. If the
target is already built, the command will not execute.
add_custom_command(TARGET <target>
PRE_BUILD | PRE_LINK | POST_BUILD
COMMAND command1 [ARGS] [args1...]
[COMMAND command2 [ARGS] [args2...] ...]
[BYPRODUCTS [files...]]
[WORKING_DIRECTORY dir]
[COMMENT comment]
[VERBATIM]
[COMMAND_EXPAND_LISTS]
[USES_TERMINAL])
This defines a new command that will be associated with building the
specified <target>. The <target> must be defined in the current
directory; targets defined in other directories may not be specified.
When the command will happen is determined by which of the following is
specified:
PRE_BUILD
This option has unique behavior for the Visual Studio Generators
<#visual-studio-generators>. When using one of the Visual
Studio generators, the command will run before any other rules
are executed within the target. With all other generators, this
option behaves the same as PRE_LINK instead. Because of this,
it is recommended to avoid using PRE_BUILD except when it is
known that a Visual Studio generator is being used.
PRE_LINK
Run after sources have been compiled but before linking the
binary or running the librarian or archiver tool of a static
library. This is not defined for targets created by the
add_custom_target() <#command:add_custom_target> command.
POST_BUILD
Run after all other rules within the target have been executed.
Projects should always specify one of the above three keywords when
using the TARGET form. See policy CMP0175 <#policy:CMP0175>.
All other keywords shown in the signature above have the same meaning
as they do for the add_custom_command(OUTPUT) form of the command. At
least one COMMAND must be given, see policy CMP0175 <#policy:CMP0175>.
Note:
Because generator expressions can be used in custom commands, it is
possible to define COMMAND lines or whole custom commands which
evaluate to empty strings for certain configurations. For Visual
Studio Generators <#visual-studio-generators> these command lines or
custom commands will be omitted for the specific configuration and
no "empty-string-command" will be added.
This allows adding individual build events for every configuration.
Added in version 3.21: Support for target-dependent generator
expressions.
Added in version 3.29: The <target> may be an ALIAS target <#alias-
targets>.
Examples: Build Events
A POST_BUILD event may be used to post-process a binary after linking.
For example, the code:
add_executable(myExe myExe.c)
add_custom_command(
TARGET myExe POST_BUILD
COMMAND someHasher -i "$<TARGET_FILE:myExe>"
-o "$<TARGET_FILE:myExe>.hash"
VERBATIM)
will run someHasher to produce a .hash file next to the executable
after linking.
Added in version 3.20: One may use generator expressions to specify
per-configuration byproducts. For example, the code:
add_library(myPlugin MODULE myPlugin.c)
add_custom_command(
TARGET myPlugin POST_BUILD
COMMAND someHasher -i "$<TARGET_FILE:myPlugin>"
--as-code "myPlugin-hash-$<CONFIG>.c"
BYPRODUCTS "myPlugin-hash-$<CONFIG>.c"
VERBATIM)
add_executable(myExe myExe.c "myPlugin-hash-$<CONFIG>.c")
will run someHasher after linking myPlugin, e.g. to produce a .c file
containing code to check the hash of myPlugin that the myExe executable
can use to verify it before loading.
Ninja Multi-Config
Added in version 3.20: add_custom_command supports the Ninja
Multi-Config <#generator:Ninja Multi-Config> generator's cross-config
capabilities. See the generator documentation for more information.
See Also
o add_custom_target() <#command:add_custom_target>
add_custom_target
Add a target with no output so it will always be built.
add_custom_target(Name [ALL] [command1 [args1...]]
[COMMAND command2 [args2...] ...]
[DEPENDS depend depend depend ... ]
[BYPRODUCTS [files...]]
[WORKING_DIRECTORY dir]
[COMMENT comment]
[JOB_POOL job_pool]
[JOB_SERVER_AWARE <bool>]
[VERBATIM] [USES_TERMINAL]
[COMMAND_EXPAND_LISTS]
[SOURCES src1 [src2...]])
Adds a target with the given name that executes the given commands.
The target has no output file and is always considered out of date even
if the commands try to create a file with the name of the target. Use
the add_custom_command() <#command:add_custom_command> command to
generate a file with dependencies. By default nothing depends on the
custom target. Use the add_dependencies() <#command:add_dependencies>
command to add dependencies to or from other targets.
The options are:
ALL Indicate that this target should be added to the default build
target so that it will be run every time (the command cannot be
called ALL).
BYPRODUCTS
Added in version 3.2.
Specify the files the command is expected to produce but whose
modification time may or may not be updated on subsequent
builds. If a byproduct name is a relative path it will be
interpreted relative to the build tree directory corresponding
to the current source directory. Each byproduct file will be
marked with the GENERATED <#prop_sf:GENERATED> source file
property automatically.
See policy CMP0058 <#policy:CMP0058> for the motivation behind
this feature.
Explicit specification of byproducts is supported by the Ninja
<#generator:Ninja> generator to tell the ninja build tool how to
regenerate byproducts when they are missing. It is also useful
when other build rules (e.g. custom commands) depend on the
byproducts. Ninja requires a build rule for any generated file
on which another rule depends even if there are order-only
dependencies to ensure the byproducts will be available before
their dependents build.
The Makefile Generators <#makefile-generators> will remove
BYPRODUCTS and other GENERATED <#prop_sf:GENERATED> files during
make clean.
Added in version 3.20: Arguments to BYPRODUCTS may use a
restricted set of generator expressions <#manual:cmake-
generator-expressions(7)>. Target-dependent expressions <#
target-dependent-expressions> are not permitted.
Changed in version 3.28: In custom targets using File Sets <#
file-sets>, byproducts are now considered private unless they
are listed in a non-private file set. See policy CMP0154 <#
policy:CMP0154>.
COMMAND
Specify the command-line(s) to execute at build time. If more
than one COMMAND is specified they will be executed in order,
but not necessarily composed into a stateful shell or batch
script. (To run a full script, use the configure_file() <#
command:configure_file> command or the file(GENERATE) <#
generate> command to create it, and then specify a COMMAND to
launch it.)
If COMMAND specifies an executable target name (created by the
add_executable() <#command:add_executable> command), it will
automatically be replaced by the location of the executable
created at build time if either of the following is true:
o The target is not being cross-compiled (i.e. the
CMAKE_CROSSCOMPILING <#variable:CMAKE_CROSSCOMPILING> variable
is not set to true).
o Added in version 3.6: The target is being cross-compiled and
an emulator is provided (i.e. its CROSSCOMPILING_EMULATOR <#
prop_tgt:CROSSCOMPILING_EMULATOR> target property is set). In
this case, the contents of CROSSCOMPILING_EMULATOR <#
prop_tgt:CROSSCOMPILING_EMULATOR> will be prepended to the
command before the location of the target executable.
If neither of the above conditions are met, it is assumed that
the command name is a program to be found on the PATH at build
time.
Arguments to COMMAND may use generator expressions <#
manual:cmake-generator-expressions(7)>. Use the TARGET_FILE <#
genex:TARGET_FILE> generator expression to refer to the location
of a target later in the command line (i.e. as a command
argument rather than as the command to execute).
Whenever one of the following target based generator expressions
are used as a command to execute or is mentioned in a command
argument, a target-level dependency will be added automatically
so that the mentioned target will be built before this custom
target (see policy CMP0112 <#policy:CMP0112>).
o TARGET_FILE
o TARGET_LINKER_FILE
o TARGET_SONAME_FILE
o TARGET_PDB_FILE
The command and arguments are optional and if not specified an
empty target will be created.
COMMENT
Display the given message before the commands are executed at
build time.
Added in version 3.26: Arguments to COMMENT may use generator
expressions <#manual:cmake-generator-expressions(7)>.
DEPENDS
Reference files and outputs of custom commands created with
add_custom_command() <#command:add_custom_command> command calls
in the same directory (CMakeLists.txt file). They will be
brought up to date when the target is built.
Changed in version 3.16: A target-level dependency is added if
any dependency is a byproduct of a target or any of its build
events in the same directory to ensure the byproducts will be
available before this target is built.
Use the add_dependencies() <#command:add_dependencies> command
to add dependencies on other targets.
COMMAND_EXPAND_LISTS
Added in version 3.8.
Lists in COMMAND arguments will be expanded, including those
created with generator expressions <#manual:cmake-generator-
expressions(7)>, allowing COMMAND arguments such as ${CC}
"-I$<JOIN:$<TARGET_PROPERTY:foo,INCLUDE_DIRECTORIES>,;-I>"
foo.cc to be properly expanded.
JOB_POOL
Added in version 3.15.
Specify a pool <#prop_gbl:JOB_POOLS> for the Ninja <#
generator:Ninja> generator. Incompatible with USES_TERMINAL,
which implies the console pool. Using a pool that is not
defined by JOB_POOLS <#prop_gbl:JOB_POOLS> causes an error by
ninja at build time.
JOB_SERVER_AWARE
Added in version 3.28.
Specify that the command is GNU Make job server aware.
For the Unix Makefiles <#generator:Unix Makefiles>, MSYS
Makefiles <#generator:MSYS Makefiles>, and MinGW Makefiles <#
generator:MinGW Makefiles> generators this will add the + prefix
to the recipe line. See the GNU Make Documentation <https://www
.gnu.org/software/make/manual/html_node/MAKE-Variable.html> for
more information.
This option is silently ignored by other generators.
SOURCES
Specify additional source files to be included in the custom
target. Specified source files will be added to IDE project
files for convenience in editing even if they have no build
rules.
VERBATIM
All arguments to the commands will be escaped properly for the
build tool so that the invoked command receives each argument
unchanged. Note that one level of escapes is still used by the
CMake language processor before add_custom_target even sees the
arguments. Use of VERBATIM is recommended as it enables correct
behavior. When VERBATIM is not given the behavior is platform
specific because there is no protection of tool-specific special
characters.
USES_TERMINAL
Added in version 3.2.
The command will be given direct access to the terminal if
possible. With the Ninja <#generator:Ninja> generator, this
places the command in the console pool <#prop_gbl:JOB_POOLS>.
WORKING_DIRECTORY
Execute the command with the given current working directory.
If it is a relative path it will be interpreted relative to the
build tree directory corresponding to the current source
directory.
Added in version 3.13: Arguments to WORKING_DIRECTORY may use
generator expressions <#manual:cmake-generator-expressions(7)>.
Ninja Multi-Config
Added in version 3.20: add_custom_target supports the Ninja
Multi-Config <#generator:Ninja Multi-Config> generator's cross-config
capabilities. See the generator documentation for more information.
See Also
o add_custom_command() <#command:add_custom_command>
add_definitions
Add -D define flags to the compilation of source files.
add_definitions(-DFOO -DBAR ...)
Adds definitions to the compiler command line for targets in the
current directory, whether added before or after this command is
invoked, and for the ones in sub-directories added after. This command
can be used to add any flags, but it is intended to add preprocessor
definitions.
Note:
This command has been superseded by alternatives:
o Use add_compile_definitions() <#command:add_compile_definitions>
to add preprocessor definitions.
o Use include_directories() <#command:include_directories> to add
include directories.
o Use add_compile_options() <#command:add_compile_options> to add
other options.
Flags beginning in -D or /D that look like preprocessor definitions are
automatically added to the COMPILE_DEFINITIONS <#
prop_dir:COMPILE_DEFINITIONS> directory property for the current
directory. Definitions with non-trivial values may be left in the set
of flags instead of being converted for reasons of backwards
compatibility. See documentation of the directory <#
prop_dir:COMPILE_DEFINITIONS>, target <#prop_tgt:COMPILE_DEFINITIONS>,
source file <#prop_sf:COMPILE_DEFINITIONS> COMPILE_DEFINITIONS
properties for details on adding preprocessor definitions to specific
scopes and configurations.
See Also
o The cmake-buildsystem(7) <#manual:cmake-buildsystem(7)> manual for
more on defining buildsystem properties.
add_dependencies
Add a dependency between top-level targets.
add_dependencies(<target> [<target-dependency>]...)
Makes a top-level <target> depend on other top-level targets to ensure
that they build before <target> does. A top-level target is one
created by one of the add_executable() <#command:add_executable>,
add_library() <#command:add_library>, or add_custom_target() <#
command:add_custom_target> commands (but not targets generated by CMake
like install).
Dependencies added to an imported target <#imported-targets> or an
interface library <#interface-libraries> are followed transitively in
its place since the target itself does not build.
Added in version 3.3: Allow adding dependencies to interface libraries.
Added in version 3.8: Dependencies will populate the
MANUALLY_ADDED_DEPENDENCIES <#prop_tgt:MANUALLY_ADDED_DEPENDENCIES>
property of <target>.
Changed in version 3.9: The Ninja Generators <#ninja-generators> use
weaker ordering than other generators in order to improve available
concurrency. They only guarantee that the dependencies' custom
commands are finished before sources in <target> start compiling; this
ensures generated sources are available.
See Also
o The DEPENDS option of add_custom_target() <#
command:add_custom_target> and add_custom_command() <#
command:add_custom_command> commands for adding file-level
dependencies in custom rules.
o The OBJECT_DEPENDS <#prop_sf:OBJECT_DEPENDS> source file property to
add file-level dependencies to object files.
add_executable
Add an executable to the project using the specified source files.
Normal Executables
add_executable(<name> <options>... <sources>...)
Add an executable target called <name> to be built from the
source files listed in the command invocation.
The options are:
WIN32 Set the WIN32_EXECUTABLE <#prop_tgt:WIN32_EXECUTABLE>
target property automatically. See documentation of that
target property for details.
MACOSX_BUNDLE
Set the MACOSX_BUNDLE <#prop_tgt:MACOSX_BUNDLE> target
property automatically. See documentation of that target
property for details.
EXCLUDE_FROM_ALL
Set the EXCLUDE_FROM_ALL <#prop_tgt:EXCLUDE_FROM_ALL>
target property automatically. See documentation of that
target property for details.
The <name> corresponds to the logical target name and must be globally
unique within a project. The actual file name of the executable built
is constructed based on conventions of the native platform (such as
<name>.exe or just <name>).
Added in version 3.1: Source arguments to add_executable may use
"generator expressions" with the syntax $<...>. See the
cmake-generator-expressions(7) <#manual:cmake-generator-expressions(7)>
manual for available expressions.
Added in version 3.11: The source files can be omitted if they are
added later using target_sources() <#command:target_sources>.
By default the executable file will be created in the build tree
directory corresponding to the source tree directory in which the
command was invoked. See documentation of the RUNTIME_OUTPUT_DIRECTORY
<#prop_tgt:RUNTIME_OUTPUT_DIRECTORY> target property to change this
location. See documentation of the OUTPUT_NAME <#prop_tgt:OUTPUT_NAME>
target property to change the <name> part of the final file name.
See the cmake-buildsystem(7) <#manual:cmake-buildsystem(7)> manual for
more on defining buildsystem properties.
See also HEADER_FILE_ONLY <#prop_sf:HEADER_FILE_ONLY> on what to do if
some sources are pre-processed, and you want to have the original
sources reachable from within IDE.
Imported Executables
add_executable(<name> IMPORTED [GLOBAL])
Add an IMPORTED executable target <#imported-targets> to
reference an executable file located outside the project. The
target name may be referenced like any target built within the
project, except that by default it is visible only in the
directory in which it is created, and below.
The options are:
GLOBAL Make the target name globally visible.
No rules are generated to build imported targets, and the IMPORTED <#
prop_tgt:IMPORTED> target property is True. Imported executables are
useful for convenient reference from commands like add_custom_command()
<#command:add_custom_command>.
Details about the imported executable are specified by setting
properties whose names begin in IMPORTED_. The most important such
property is IMPORTED_LOCATION <#prop_tgt:IMPORTED_LOCATION> (and its
per-configuration version IMPORTED_LOCATION_<CONFIG> <#
prop_tgt:IMPORTED_LOCATION_<CONFIG>>) which specifies the location of
the main executable file on disk. See documentation of the IMPORTED_*
properties for more information.
Alias Executables
add_executable(<name> ALIAS <target>)
Creates an Alias Target <#alias-targets>, such that <name> can
be used to refer to <target> in subsequent commands. The <name>
does not appear in the generated buildsystem as a make target.
The <target> may not be an ALIAS.
Added in version 3.11: An ALIAS can target a GLOBAL Imported Target <#
imported-targets>
Added in version 3.18: An ALIAS can target a non-GLOBAL Imported
Target. Such alias is scoped to the directory in which it is created
and subdirectories. The ALIAS_GLOBAL <#prop_tgt:ALIAS_GLOBAL> target
property can be used to check if the alias is global or not.
ALIAS targets can be used as targets to read properties from,
executables for custom commands and custom targets. They can also be
tested for existence with the regular if(TARGET) <#target> subcommand.
The <name> may not be used to modify properties of <target>, that is,
it may not be used as the operand of set_property() <#
command:set_property>, set_target_properties() <#
command:set_target_properties>, target_link_libraries() <#
command:target_link_libraries> etc. An ALIAS target may not be
installed or exported.
See Also
o add_library() <#command:add_library>
add_library
Add a library to the project using the specified source files.
Normal Libraries
add_library(<name> [<type>] [EXCLUDE_FROM_ALL] <sources>...)
Add a library target called <name> to be built from the source
files listed in the command invocation.
The optional <type> specifies the type of library to be created:
STATIC An archive of object files for use when linking other
targets.
SHARED A dynamic library that may be linked by other targets and
loaded at runtime.
MODULE A plugin that may not be linked by other targets, but may
be dynamically loaded at runtime using dlopen-like
functionality.
If no <type> is given the default is STATIC or SHARED based on
the value of the BUILD_SHARED_LIBS <#variable:BUILD_SHARED_LIBS>
variable.
The options are:
EXCLUDE_FROM_ALL
Set the EXCLUDE_FROM_ALL <#prop_tgt:EXCLUDE_FROM_ALL>
target property automatically. See documentation of that
target property for details.
The <name> corresponds to the logical target name and must be globally
unique within a project. The actual file name of the library built is
constructed based on conventions of the native platform (such as
lib<name>.a or <name>.lib).
Added in version 3.1: Source arguments to add_library may use
"generator expressions" with the syntax $<...>. See the
cmake-generator-expressions(7) <#manual:cmake-generator-expressions(7)>
manual for available expressions.
Added in version 3.11: The source files can be omitted if they are
added later using target_sources() <#command:target_sources>.
For SHARED and MODULE libraries the POSITION_INDEPENDENT_CODE <#
prop_tgt:POSITION_INDEPENDENT_CODE> target property is set to ON
automatically. A SHARED library may be marked with the FRAMEWORK <#
prop_tgt:FRAMEWORK> target property to create an macOS Framework.
Added in version 3.8: A STATIC library may be marked with the FRAMEWORK
<#prop_tgt:FRAMEWORK> target property to create a static Framework.
If a library does not export any symbols, it must not be declared as a
SHARED library. For example, a Windows resource DLL or a managed
C++/CLI DLL that exports no unmanaged symbols would need to be a MODULE
library. This is because CMake expects a SHARED library to always have
an associated import library on Windows.
By default the library file will be created in the build tree directory
corresponding to the source tree directory in which the command was
invoked. See documentation of the ARCHIVE_OUTPUT_DIRECTORY <#
prop_tgt:ARCHIVE_OUTPUT_DIRECTORY>, LIBRARY_OUTPUT_DIRECTORY <#
prop_tgt:LIBRARY_OUTPUT_DIRECTORY>, and RUNTIME_OUTPUT_DIRECTORY <#
prop_tgt:RUNTIME_OUTPUT_DIRECTORY> target properties to change this
location. See documentation of the OUTPUT_NAME <#prop_tgt:OUTPUT_NAME>
target property to change the <name> part of the final file name.
See the cmake-buildsystem(7) <#manual:cmake-buildsystem(7)> manual for
more on defining buildsystem properties.
See also HEADER_FILE_ONLY <#prop_sf:HEADER_FILE_ONLY> on what to do if
some sources are pre-processed, and you want to have the original
sources reachable from within IDE.
Changed in version 3.30: On platforms that do not support shared
libraries, add_library now fails on calls creating SHARED libraries
instead of automatically converting them to STATIC libraries as before.
See policy CMP0164 <#policy:CMP0164>.
Object Libraries
add_library(<name> OBJECT <sources>...)
Add an Object Library <#object-libraries> to compile source
files without archiving or linking their object files into a
library.
Other targets created by add_library or add_executable() <#
command:add_executable> may reference the objects using an expression
of the form $<TARGET_OBJECTS:objlib> <#genex:TARGET_OBJECTS> as a
source, where objlib is the object library name. For example:
add_library(... $<TARGET_OBJECTS:objlib> ...)
add_executable(... $<TARGET_OBJECTS:objlib> ...)
will include objlib's object files in a library and an executable along
with those compiled from their own sources. Object libraries may
contain only sources that compile, header files, and other files that
would not affect linking of a normal library (e.g. .txt). They may
contain custom commands generating such sources, but not PRE_BUILD,
PRE_LINK, or POST_BUILD commands. Some native build systems (such as
Xcode) may not like targets that have only object files, so consider
adding at least one real source file to any target that references
$<TARGET_OBJECTS:objlib> <#genex:TARGET_OBJECTS>.
Added in version 3.12: Object libraries can be linked to with
target_link_libraries() <#command:target_link_libraries>.
Interface Libraries
add_library(<name> INTERFACE)
Add an Interface Library <#interface-libraries> target that may
specify usage requirements for dependents but does not compile
sources and does not produce a library artifact on disk.
An interface library with no source files is not included as a
target in the generated buildsystem. However, it may have
properties set on it and it may be installed and exported.
Typically, INTERFACE_* properties are populated on an interface
target using the commands:
o set_property() <#command:set_property>,
o target_link_libraries(INTERFACE) <#
command:target_link_libraries>,
o target_link_options(INTERFACE) <#command:target_link_options>,
o target_include_directories(INTERFACE) <#
command:target_include_directories>,
o target_compile_options(INTERFACE) <#
command:target_compile_options>,
o target_compile_definitions(INTERFACE) <#
command:target_compile_definitions>, and
o target_sources(INTERFACE) <#command:target_sources>,
and then it is used as an argument to target_link_libraries() <#
command:target_link_libraries> like any other target.
Added in version 3.15: An interface library can have
PUBLIC_HEADER <#prop_tgt:PUBLIC_HEADER> and PRIVATE_HEADER <#
prop_tgt:PRIVATE_HEADER> properties. The headers specified by
those properties can be installed using the install(TARGETS) <#
targets> command.
add_library(<name> INTERFACE [EXCLUDE_FROM_ALL] <sources>...)
Added in version 3.19.
Add an Interface Library <#interface-libraries> target with
source files (in addition to usage requirements and properties
as documented by the above signature). Source files may be
listed directly in the add_library call or added later by calls
to target_sources() <#command:target_sources> with the PRIVATE
or PUBLIC keywords.
If an interface library has source files (i.e. the SOURCES <#
prop_tgt:SOURCES> target property is set), or header sets (i.e.
the HEADER_SETS <#prop_tgt:HEADER_SETS> target property is set),
it will appear in the generated buildsystem as a build target
much like a target defined by the add_custom_target() <#
command:add_custom_target> command. It does not compile any
sources, but does contain build rules for custom commands
created by the add_custom_command() <#
command:add_custom_command> command.
The options are:
EXCLUDE_FROM_ALL
Set the EXCLUDE_FROM_ALL <#prop_tgt:EXCLUDE_FROM_ALL>
target property automatically. See documentation of that
target property for details.
Note:
In most command signatures where the INTERFACE keyword
appears, the items listed after it only become part of that
target's usage requirements and are not part of the target's
own settings. However, in this signature of add_library, the
INTERFACE keyword refers to the library type only. Sources
listed after it in the add_library call are PRIVATE to the
interface library and do not appear in its INTERFACE_SOURCES
<#prop_tgt:INTERFACE_SOURCES> target property.
Imported Libraries
add_library(<name> <type> IMPORTED [GLOBAL])
Add an IMPORTED library target <#imported-targets> called
<name>. The target name may be referenced like any target built
within the project, except that by default it is visible only in
the directory in which it is created, and below.
The <type> must be one of:
STATIC, SHARED, MODULE, UNKNOWN
References a library file located outside the project.
The IMPORTED_LOCATION <#prop_tgt:IMPORTED_LOCATION>
target property (or its per-configuration variant
IMPORTED_LOCATION_<CONFIG> <#
prop_tgt:IMPORTED_LOCATION_<CONFIG>>) specifies the
location of the main library file on disk:
o For a SHARED library on most non-Windows platforms, the
main library file is the .so or .dylib file used by
both linkers and dynamic loaders. If the referenced
library file has a SONAME (or on macOS, has a
LC_ID_DYLIB starting in @rpath/), the value of that
field should be set in the IMPORTED_SONAME <#
prop_tgt:IMPORTED_SONAME> target property. If the
referenced library file does not have a SONAME, but the
platform supports it, then the IMPORTED_NO_SONAME <#
prop_tgt:IMPORTED_NO_SONAME> target property should be
set.
o For a SHARED library on Windows, the IMPORTED_IMPLIB <#
prop_tgt:IMPORTED_IMPLIB> target property (or its
per-configuration variant IMPORTED_IMPLIB_<CONFIG> <#
prop_tgt:IMPORTED_IMPLIB_<CONFIG>>) specifies the
location of the DLL import library file (.lib or
.dll.a) on disk, and the IMPORTED_LOCATION is the
location of the .dll runtime library (and is optional,
but needed by the TARGET_RUNTIME_DLLS <#
genex:TARGET_RUNTIME_DLLS> generator expression).
Additional usage requirements may be specified in
INTERFACE_* properties.
An UNKNOWN library type is typically only used in the
implementation of Find Modules <#find-modules>. It
allows the path to an imported library (often found using
the find_library() <#command:find_library> command) to be
used without having to know what type of library it is.
This is especially useful on Windows where a static
library and a DLL's import library both have the same
file extension.
OBJECT References a set of object files located outside the
project. The IMPORTED_OBJECTS <#
prop_tgt:IMPORTED_OBJECTS> target property (or its
per-configuration variant IMPORTED_OBJECTS_<CONFIG> <#
prop_tgt:IMPORTED_OBJECTS_<CONFIG>>) specifies the
locations of object files on disk. Additional usage
requirements may be specified in INTERFACE_* properties.
INTERFACE
Does not reference any library or object files on disk,
but may specify usage requirements in INTERFACE_*
properties.
The options are:
GLOBAL Make the target name globally visible.
No rules are generated to build imported targets, and the IMPORTED <#
prop_tgt:IMPORTED> target property is True. Imported libraries are
useful for convenient reference from commands like
target_link_libraries() <#command:target_link_libraries>.
Details about the imported library are specified by setting properties
whose names begin in IMPORTED_ and INTERFACE_. See documentation of
such properties for more information.
Alias Libraries
add_library(<name> ALIAS <target>)
Creates an Alias Target <#alias-targets>, such that <name> can
be used to refer to <target> in subsequent commands. The <name>
does not appear in the generated buildsystem as a make target.
The <target> may not be an ALIAS.
Added in version 3.11: An ALIAS can target a GLOBAL Imported Target <#
imported-targets>
Added in version 3.18: An ALIAS can target a non-GLOBAL Imported
Target. Such alias is scoped to the directory in which it is created
and below. The ALIAS_GLOBAL <#prop_tgt:ALIAS_GLOBAL> target property
can be used to check if the alias is global or not.
ALIAS targets can be used as linkable targets and as targets to read
properties from. They can also be tested for existence with the
regular if(TARGET) <#target> subcommand. The <name> may not be used to
modify properties of <target>, that is, it may not be used as the
operand of set_property() <#command:set_property>,
set_target_properties() <#command:set_target_properties>,
target_link_libraries() <#command:target_link_libraries> etc. An ALIAS
target may not be installed or exported.
See Also
o add_executable() <#command:add_executable>
add_link_options
Added in version 3.13.
Add options to the link step for executable, shared library or module
library targets in the current directory and below that are added after
this command is invoked.
add_link_options(<option> ...)
This command can be used to add any link options, but alternative
commands exist to add libraries (target_link_libraries() <#
command:target_link_libraries> or link_libraries() <#
command:link_libraries>). See documentation of the directory <#
prop_dir:LINK_OPTIONS> and target <#prop_tgt:LINK_OPTIONS> LINK_OPTIONS
properties.
Note:
This command cannot be used to add options for static library
targets, since they do not use a linker. To add archiver or MSVC
librarian flags, see the STATIC_LIBRARY_OPTIONS <#
prop_tgt:STATIC_LIBRARY_OPTIONS> target property.
Arguments to add_link_options may use generator expressions with the
syntax $<...>. See the cmake-generator-expressions(7) <#manual:cmake-
generator-expressions(7)> manual for available expressions. See the
cmake-buildsystem(7) <#manual:cmake-buildsystem(7)> manual for more on
defining buildsystem properties.
Host And Device Specific Link Options
Added in version 3.18: When a device link step is involved, which is
controlled by CUDA_SEPARABLE_COMPILATION <#
prop_tgt:CUDA_SEPARABLE_COMPILATION> and CUDA_RESOLVE_DEVICE_SYMBOLS <#
prop_tgt:CUDA_RESOLVE_DEVICE_SYMBOLS> properties and policy CMP0105 <#
policy:CMP0105>, the raw options will be delivered to the host and
device link steps (wrapped in -Xcompiler or equivalent for device
link). Options wrapped with $<DEVICE_LINK:...> <#genex:DEVICE_LINK>
generator expression will be used only for the device link step.
Options wrapped with $<HOST_LINK:...> <#genex:HOST_LINK> generator
expression will be used only for the host link step.
Option De-duplication
The final set of options used for a target is constructed by
accumulating options from the current target and the usage requirements
of its dependencies. The set of options is de-duplicated to avoid
repetition.
Added in version 3.12: While beneficial for individual options, the
de-duplication step can break up option groups. For example, -option A
-option B becomes -option A B. One may specify a group of options
using shell-like quoting along with a SHELL: prefix. The SHELL: prefix
is dropped, and the rest of the option string is parsed using the
separate_arguments() <#command:separate_arguments> UNIX_COMMAND mode.
For example, "SHELL:-option A" "SHELL:-option B" becomes -option A
-option B.
Handling Compiler Driver Differences
To pass options to the linker tool, each compiler driver has its own
syntax. The LINKER: prefix and , separator can be used to specify, in
a portable way, options to pass to the linker tool. LINKER: is replaced
by the appropriate driver option and , by the appropriate driver
separator. The driver prefix and driver separator are given by the
values of the CMAKE_<LANG>_LINKER_WRAPPER_FLAG <#
variable:CMAKE_<LANG>_LINKER_WRAPPER_FLAG> and
CMAKE_<LANG>_LINKER_WRAPPER_FLAG_SEP <#
variable:CMAKE_<LANG>_LINKER_WRAPPER_FLAG_SEP> variables.
For example, "LINKER:-z,defs" becomes -Xlinker -z -Xlinker defs for
Clang and -Wl,-z,defs for GNU GCC.
The LINKER: prefix can be specified as part of a SHELL: prefix
expression.
The LINKER: prefix supports, as an alternative syntax, specification of
arguments using the SHELL: prefix and space as separator. The previous
example then becomes "LINKER:SHELL:-z defs".
Note:
Specifying the SHELL: prefix anywhere other than at the beginning of
the LINKER: prefix is not supported.
See Also
o link_libraries() <#command:link_libraries>
o target_link_libraries() <#command:target_link_libraries>
o target_link_options() <#command:target_link_options>
o CMAKE_<LANG>_FLAGS <#variable:CMAKE_<LANG>_FLAGS> and
CMAKE_<LANG>_FLAGS_<CONFIG> <#variable:CMAKE_<LANG>_FLAGS_<CONFIG>>
add language-wide flags passed to all invocations of the compiler.
This includes invocations that drive compiling and those that drive
linking.
add_subdirectory
Add a subdirectory to the build.
add_subdirectory(source_dir [binary_dir] [EXCLUDE_FROM_ALL] [SYSTEM])
Adds a subdirectory to the build. The source_dir specifies the
directory in which the source CMakeLists.txt and code files are
located. If it is a relative path, it will be evaluated with respect
to the current directory (the typical usage), but it may also be an
absolute path. The binary_dir specifies the directory in which to
place the output files. If it is a relative path, it will be evaluated
with respect to the current output directory, but it may also be an
absolute path. If binary_dir is not specified, the value of
source_dir, before expanding any relative path, will be used (the
typical usage). The CMakeLists.txt file in the specified source
directory will be processed immediately by CMake before processing in
the current input file continues beyond this command.
If the EXCLUDE_FROM_ALL argument is provided then the EXCLUDE_FROM_ALL
<#prop_dir:EXCLUDE_FROM_ALL> property will be set on the added
directory. This will exclude the directory from a default build. See
the directory property EXCLUDE_FROM_ALL <#prop_dir:EXCLUDE_FROM_ALL>
for full details.
Added in version 3.25: If the SYSTEM argument is provided, the SYSTEM
<#prop_dir:SYSTEM> directory property of the subdirectory will be set
to true. This property is used to initialize the SYSTEM <#
prop_tgt:SYSTEM> property of each non-imported target created in that
subdirectory.
add_test
Add a test to the project to be run by ctest(1) <#manual:ctest(1)>.
add_test(NAME <name> COMMAND <command> [<arg>...]
[CONFIGURATIONS <config>...]
[WORKING_DIRECTORY <dir>]
[COMMAND_EXPAND_LISTS])
Adds a test called <name>. The test name may contain arbitrary
characters, expressed as a Quoted Argument <#quoted-argument> or
Bracket Argument <#bracket-argument> if necessary. See policy CMP0110
<#policy:CMP0110>.
CMake only generates tests if the enable_testing() <#
command:enable_testing> command has been invoked. The CTest <#
module:CTest> module invokes enable_testing automatically unless
BUILD_TESTING is set to OFF.
Tests added with the add_test(NAME) signature support using generator
expressions <#manual:cmake-generator-expressions(7)> in test properties
set by set_property(TEST) <#command:set_property> or
set_tests_properties() <#command:set_tests_properties>. Test properties
may only be set in the directory the test is created in.
add_test options are:
COMMAND
Specify the test command-line.
If <command> specifies an executable target created by
add_executable() <#command:add_executable>:
o It will automatically be replaced by the location of the
executable created at build time.
o Added in version 3.3: The target's CROSSCOMPILING_EMULATOR <#
prop_tgt:CROSSCOMPILING_EMULATOR>, if set, will be used to run
the command on the host:
<emulator> <command>
Changed in version 3.29: The emulator is used only when
cross-compiling <#variable:CMAKE_CROSSCOMPILING>. See policy
CMP0158 <#policy:CMP0158>.
o Added in version 3.29: The target's TEST_LAUNCHER <#
prop_tgt:TEST_LAUNCHER>, if set, will be used to launch the
command:
<launcher> <command>
If the CROSSCOMPILING_EMULATOR <#
prop_tgt:CROSSCOMPILING_EMULATOR> is also set, both are used:
<launcher> <emulator> <command>
The command may be specified using generator expressions <#
manual:cmake-generator-expressions(7)>.
CONFIGURATIONS
Restrict execution of the test only to the named configurations.
WORKING_DIRECTORY
Set the test property WORKING_DIRECTORY <#
prop_test:WORKING_DIRECTORY> in which to execute the test. If
not specified, the test will be run in CMAKE_CURRENT_BINARY_DIR
<#variable:CMAKE_CURRENT_BINARY_DIR>. The working directory may
be specified using generator expressions <#manual:cmake-
generator-expressions(7)>.
COMMAND_EXPAND_LISTS
Added in version 3.16.
Lists in COMMAND arguments will be expanded, including those
created with generator expressions <#manual:cmake-generator-
expressions(7)>.
If the test command exits with code 0 the test passes. Non-zero exit
code is a "failed" test. The test property WILL_FAIL <#
prop_test:WILL_FAIL> inverts this logic. Note that system-level test
failures such as segmentation faults or heap errors will still fail the
test even if WILL_FAIL is true. Output written to stdout or stderr is
captured by ctest(1) <#manual:ctest(1)> and only affects the pass/fail
status via the PASS_REGULAR_EXPRESSION <#
prop_test:PASS_REGULAR_EXPRESSION>, FAIL_REGULAR_EXPRESSION <#
prop_test:FAIL_REGULAR_EXPRESSION>, or SKIP_REGULAR_EXPRESSION <#
prop_test:SKIP_REGULAR_EXPRESSION> test properties.
Added in version 3.16: Added SKIP_REGULAR_EXPRESSION <#
prop_test:SKIP_REGULAR_EXPRESSION> property.
Example usage:
add_test(NAME mytest
COMMAND testDriver --config $<CONFIG>
--exe $<TARGET_FILE:myexe>)
This creates a test mytest whose command runs a testDriver tool passing
the configuration name and the full path to the executable file
produced by target myexe.
----
The command syntax above is recommended over the older, less flexible
form:
add_test(<name> <command> [<arg>...])
Add a test called <name> with the given command-line.
Unlike the above NAME signature, target names are not supported in the
command-line. Furthermore, tests added with this signature do not
support generator expressions <#manual:cmake-generator-expressions(7)>
in the command-line or test properties.
aux_source_directory
Find all source files in a directory.
aux_source_directory(<dir> <variable>)
Collects the names of all the source files in the specified directory
and stores the list in the <variable> provided. This command is
intended to be used by projects that use explicit template
instantiation. Template instantiation files can be stored in a
Templates subdirectory and collected automatically using this command
to avoid manually listing all instantiations.
It is tempting to use this command to avoid writing the list of source
files for a library or executable target. While this seems to work,
there is no way for CMake to generate a build system that knows when a
new source file has been added. Normally the generated build system
knows when it needs to rerun CMake because the CMakeLists.txt file is
modified to add a new source. When the source is just added to the
directory without modifying this file, one would have to manually rerun
CMake to generate a build system incorporating the new file.
build_command
Get a command line to build the current project. This is mainly
intended for internal use by the CTest <#module:CTest> module.
build_command(<variable>
[CONFIGURATION <config>]
[PARALLEL_LEVEL <parallel>]
[TARGET <target>]
[PROJECT_NAME <projname>] # legacy, causes warning
)
Sets the given <variable> to a command-line string of the form:
<cmake> --build . [--config <config>] [--parallel <parallel>] [--target <target>...] [-- -i]
where <cmake> is the location of the cmake(1) <#manual:cmake(1)>
command-line tool, and <config>, <parallel> and <target> are the values
provided to the CONFIGURATION, PARALLEL_LEVEL and TARGET options, if
any. The trailing -- -i option is added for Makefile Generators <#
makefile-generators> if policy CMP0061 <#policy:CMP0061> is not set to
NEW.
When invoked, this cmake --build <#cmdoption-cmake-build> command line
will launch the underlying build system tool.
Added in version 3.21: The PARALLEL_LEVEL argument can be used to set
the --parallel <#cmdoption-cmake-build-j> flag.
build_command(<cachevariable> <makecommand>)
This second signature is deprecated, but still available for backwards
compatibility. Use the first signature instead.
It sets the given <cachevariable> to a command-line string as above but
without the --target <#cmdoption-cmake-build-t> option. The
<makecommand> is ignored but should be the full path to devenv, nmake,
make or one of the end user build tools for legacy invocations.
Note:
In CMake versions prior to 3.0 this command returned a command line
that directly invokes the native build tool for the current
generator. Their implementation of the PROJECT_NAME option had no
useful effects, so CMake now warns on use of the option.
cmake_file_api
Added in version 3.27.
Enables interacting with the CMake file API <#manual:cmake-file-
api(7)>.
cmake_file_api(QUERY ...)
The QUERY subcommand adds a file API query for the current CMake
invocation.
cmake_file_api(
QUERY
API_VERSION <version>
[CODEMODEL <versions>...]
[CACHE <versions>...]
[CMAKEFILES <versions>...]
[TOOLCHAINS <versions>...]
)
The API_VERSION must always be given. Currently, the only
supported value for <version> is 1. See API v1 <#file-api-v1>
for details of the reply content and location.
Each of the optional keywords CODEMODEL, CACHE, CMAKEFILES and
TOOLCHAINS correspond to one of the object kinds that can be
requested by the project. The configureLog object kind cannot
be set with this command, since it must be set before CMake
starts reading the top level CMakeLists.txt file.
For each of the optional keywords, the <versions> list must
contain one or more version values of the form major or
major.minor, where major and minor are integers. Projects
should list the versions they accept in their preferred order,
as only the first supported value from the list will be
selected. The command will ignore versions with a major version
higher than any major version it supports for that object kind.
It will raise an error if it encounters an invalid version
number, or if none of the requested versions is supported.
For each type of object kind requested, a query equivalent to a
shared, stateless query will be added internally. No query file
will be created in the file system. The reply will be written
to the file system at generation time.
It is not an error to add a query for the same thing more than
once, whether from query files or from multiple calls to
cmake_file_api(QUERY). The final set of queries will be a
merged combination of all queries specified on disk and queries
submitted by the project.
Example
A project may want to use replies from the file API at build time to
implement some form of verification task. Instead of relying on
something outside of CMake to create a query file, the project can use
cmake_file_api(QUERY) to request the required information for the
current run. It can then create a custom command to run at build time,
knowing that the requested information should always be available.
cmake_file_api(
QUERY
API_VERSION 1
CODEMODEL 2.3
TOOLCHAINS 1
)
add_custom_target(verify_project
COMMAND ${CMAKE_COMMAND}
-D BUILD_DIR=${CMAKE_BINARY_DIR}
-D CONFIG=$<CONFIG>
-P ${CMAKE_CURRENT_SOURCE_DIR}/verify_project.cmake
)
create_test_sourcelist
Create a test driver program that links together many small tests into
a single executable. This is useful when building static executables
with large libraries to shrink the total required size.
create_test_sourcelist(<sourceListName> <driverName> <test>...
<options>...)
Generate a test driver source file from a list of individual
test sources and provide a combined list of sources that can be
built as an executable.
The options are:
<sourceListName>
The name of a variable in which to store the list of
source files needed to build the test driver. The list
will contain the <test>... sources and the generated
<driverName> source.
Changed in version 3.29: The test driver source is listed
by absolute path in the build tree. Previously it was
listed only as <driverName>.
<driverName>
Name of the test driver source file to be generated into
the build tree. The source file will contain a main()
program entry point that dispatches to whatever test is
named on the command line.
<test>...
Test source files to be added to the driver binary. Each
test source file must have a function in it that is the
same name as the file with the extension removed. For
example, a foo.cxx test source might contain:
int foo(int argc, char** argv)
EXTRA_INCLUDE <header>
Specify a header file to #include in the generated test
driver source.
FUNCTION <function>
Specify a function to be called with pointers to argc and
argv. The function may be provided in the EXTRA_INCLUDE
header:
void function(int* pargc, char*** pargv)
This can be used to add extra command line processing to
each test.
Additionally, some CMake variables affect test driver generation:
CMAKE_TESTDRIVER_BEFORE_TESTMAIN
Code to be placed directly before calling each test's function.
CMAKE_TESTDRIVER_AFTER_TESTMAIN
Code to be placed directly after the call to each test's
function.
define_property
Define and document custom properties.
define_property(<GLOBAL | DIRECTORY | TARGET | SOURCE |
TEST | VARIABLE | CACHED_VARIABLE>
PROPERTY <name> [INHERITED]
[BRIEF_DOCS <brief-doc> [docs...]]
[FULL_DOCS <full-doc> [docs...]]
[INITIALIZE_FROM_VARIABLE <variable>])
Defines one property in a scope for use with the set_property() <#
command:set_property> and get_property() <#command:get_property>
commands. It is mainly useful for defining the way a property is
initialized or inherited. Historically, the command also associated
documentation with a property, but that is no longer considered a
primary use case.
The first argument determines the kind of scope in which the property
should be used. It must be one of the following:
GLOBAL = associated with the global namespace
DIRECTORY = associated with one directory
TARGET = associated with one target
SOURCE = associated with one source file
TEST = associated with a test named with add_test
VARIABLE = documents a CMake language variable
CACHED_VARIABLE = documents a CMake cache variable
Note that unlike set_property() <#command:set_property> and
get_property() <#command:get_property> no actual scope needs to be
given; only the kind of scope is important.
The required PROPERTY option is immediately followed by the name of the
property being defined.
If the INHERITED option is given, then the get_property() <#
command:get_property> command will chain up to the next higher scope
when the requested property is not set in the scope given to the
command.
o DIRECTORY scope chains to its parent directory's scope, continuing
the walk up parent directories until a directory has the property set
or there are no more parents. If still not found at the top level
directory, it chains to the GLOBAL scope.
o TARGET, SOURCE and TEST properties chain to DIRECTORY scope,
including further chaining up the directories, etc. as needed.
Note that this scope chaining behavior only applies to calls to
get_property() <#command:get_property>, get_directory_property() <#
command:get_directory_property>, get_target_property() <#
command:get_target_property>, get_source_file_property() <#
command:get_source_file_property> and get_test_property() <#
command:get_test_property>. There is no inheriting behavior when
setting properties, so using APPEND or APPEND_STRING with the
set_property() <#command:set_property> command will not consider
inherited values when working out the contents to append to.
The BRIEF_DOCS and FULL_DOCS options are followed by strings to be
associated with the property as its brief and full documentation.
CMake does not use this documentation other than making it available to
the project via corresponding options to the get_property() <#
command:get_property> command.
Changed in version 3.23: The BRIEF_DOCS and FULL_DOCS options are
optional.
Added in version 3.23: The INITIALIZE_FROM_VARIABLE option specifies a
variable from which the property should be initialized. It can only be
used with target properties. The <variable> name must end with the
property name and must not begin with CMAKE_ or _CMAKE_. The property
name must contain at least one underscore. It is recommended that the
property name have a prefix specific to the project.
Property Redefinition
Once a property is defined for a particular type of scope, it cannot be
redefined. Attempts to redefine an existing property by calling
define_property() with the same scope type and property name will be
silently ignored. Defining the same property name for two different
kinds of scope is valid.
get_property() <#command:get_property> can be used to determine whether
a property is already defined for a particular kind of scope, and if
so, to examine its definition. For example:
# Initial definition
define_property(TARGET PROPERTY MY_NEW_PROP
BRIEF_DOCS "My new custom property"
)
# Later examination
get_property(my_new_prop_exists
TARGET NONE
PROPERTY MY_NEW_PROP
DEFINED
)
if(my_new_prop_exists)
get_property(my_new_prop_docs
TARGET NONE
PROPERTY MY_NEW_PROP
BRIEF_DOCS
)
# ${my_new_prop_docs} is now set to "My new custom property"
endif()
See Also
o get_property() <#command:get_property>
o set_property() <#command:set_property>
enable_language
Enable languages (CXX/C/OBJC/OBJCXX/Fortran/etc)
enable_language(<lang>... [OPTIONAL])
Enables support for the named languages in CMake. This is the same as
the project() <#command:project> command but does not create any of the
extra variables that are created by the project() <#command:project>
command.
Supported languages are C, CXX (i.e. C++), CSharp (i.e. C#), CUDA,
OBJC (i.e. Objective-C), OBJCXX (i.e. Objective-C++), Fortran, HIP,
ISPC, Swift, ASM, ASM_NASM, ASM_MARMASM, ASM_MASM, and ASM-ATT.
Added in version 3.8: Added CSharp and CUDA support.
Added in version 3.15: Added Swift support.
Added in version 3.16: Added OBJC and OBJCXX support.
Added in version 3.18: Added ISPC support.
Added in version 3.21: Added HIP support.
Added in version 3.26: Added ASM_MARMASM support.
If enabling ASM, list it last so that CMake can check whether compilers
for other languages like C work for assembly too.
The following restrictions apply to where enable_language() may be
called:
o It must be called in file scope, not in a function call.
o It must not be called before the first call to project() <#
command:project>. See policy CMP0165 <#policy:CMP0165>.
o It must be called in the highest directory common to all targets
using the named language directly for compiling sources or indirectly
through link dependencies. It is simplest to enable all needed
languages in the top-level directory of a project.
The OPTIONAL keyword is a placeholder for future implementation and
does not currently work. Instead you can use the CheckLanguage <#
module:CheckLanguage> module to verify support before enabling.
enable_testing
Enable testing for current directory and below.
enable_testing()
Enables testing for this directory and below.
This command should be in the source directory root because ctest
expects to find a test file in the build directory root.
This command is automatically invoked when the CTest <#module:CTest>
module is included, except if the BUILD_TESTING option is turned off.
See also the add_test() <#command:add_test> command.
export
Export targets or packages for outside projects to use them directly
from the current project's build tree, without installation.
See the install(EXPORT) <#export> command to export targets from an
install tree.
Synopsis
export(TARGETS <target>... [...])
export(EXPORT <export-name> [...])
export(PACKAGE <PackageName>)
export(SETUP <export-name> [...])
Exporting Targets
export(TARGETS <target>... [...])
export(TARGETS <target>... [NAMESPACE <namespace>]
[APPEND] FILE <filename> [EXPORT_LINK_INTERFACE_LIBRARIES]
[CXX_MODULES_DIRECTORY <directory>])
Creates a file <filename> that may be included by outside projects to
import targets named by <target>... from the current project's build
tree. This is useful during cross-compiling to build utility
executables that can run on the host platform in one project and then
import them into another project being compiled for the target
platform.
The file created by this command is specific to the build tree and
should never be installed. See the install(EXPORT) <#export> command
to export targets from an install tree.
The options are:
NAMESPACE <namespace>
Prepend the <namespace> string to all target names written to
the file.
APPEND Append to the file instead of overwriting it. This can be used
to incrementally export multiple targets to the same file.
EXPORT_LINK_INTERFACE_LIBRARIES
Include the contents of the properties named with the pattern
(IMPORTED_)?LINK_INTERFACE_LIBRARIES(_<CONFIG>)? in the export,
even when policy CMP0022 <#policy:CMP0022> is NEW. This is
useful to support consumers using CMake versions older than
2.8.12.
CXX_MODULES_DIRECTORY <directory>
Added in version 3.28.
Export C++ module properties to files under the given directory.
Each file will be named according to the target's export name
(without any namespace). These files will automatically be
included from the export file.
This signature requires all targets to be listed explicitly. If a
library target is included in the export, but a target to which it
links is not included, the behavior is unspecified. See the
export(EXPORT) signature to automatically export the same targets from
the build tree as install(EXPORT) <#export> would from an install tree.
Note:
Object Libraries <#object-libraries> under Xcode <#generator:Xcode>
have special handling if multiple architectures are listed in
CMAKE_OSX_ARCHITECTURES <#variable:CMAKE_OSX_ARCHITECTURES>. In
this case they will be exported as Interface Libraries <#interface-
libraries> with no object files available to clients. This is
sufficient to satisfy transitive usage requirements of other targets
that link to the object libraries in their implementation.
This command exports all Build Configurations <#build-configurations>
from the build tree. See the CMAKE_MAP_IMPORTED_CONFIG_<CONFIG> <#
variable:CMAKE_MAP_IMPORTED_CONFIG_<CONFIG>> variable to map
configurations of dependent projects to the exported configurations.
Exporting Targets to Android.mk
export(TARGETS <target>... ANDROID_MK <filename>)
Added in version 3.7.
This signature exports cmake built targets to the android ndk build
system by creating an Android.mk file that references the prebuilt
targets. The Android NDK supports the use of prebuilt libraries, both
static and shared. This allows cmake to build the libraries of a
project and make them available to an ndk build system complete with
transitive dependencies, include flags and defines required to use the
libraries. The signature takes a list of targets and puts them in the
Android.mk file specified by the <filename> given. This signature can
only be used if policy CMP0022 <#policy:CMP0022> is NEW for all targets
given. A error will be issued if that policy is set to OLD for one of
the targets.
Exporting Targets matching install(EXPORT)
export(EXPORT <export-name> [...])
export(EXPORT <export-name> [NAMESPACE <namespace>] [FILE <filename>]
[CXX_MODULES_DIRECTORY <directory>] [EXPORT_PACKAGE_DEPENDENCIES])
Creates a file <filename> that may be included by outside projects to
import targets from the current project's build tree. This is the same
as the export(TARGETS) signature, except that the targets are not
explicitly listed. Instead, it exports the targets associated with the
installation export <export-name>. Target installations may be
associated with the export <export-name> using the EXPORT option of the
install(TARGETS) <#targets> command.
EXPORT_PACKAGE_DEPENDENCIES
Note:
Experimental. Gated by
CMAKE_EXPERIMENTAL_EXPORT_PACKAGE_DEPENDENCIES.
Specify that find_dependency() <#command:find_dependency> calls
should be exported. See install(EXPORT) <#export> for details on
how this works.
Exporting Packages
export(PACKAGE <PackageName>)
export(PACKAGE <PackageName>)
Store the current build directory in the CMake user package registry
for package <PackageName>. The find_package() <#command:find_package>
command may consider the directory while searching for package
<PackageName>. This helps dependent projects find and use a package
from the current project's build tree without help from the user. Note
that the entry in the package registry that this command creates works
only in conjunction with a package configuration file
(<PackageName>Config.cmake) that works with the build tree. In some
cases, for example for packaging and for system wide installations, it
is not desirable to write the user package registry.
Changed in version 3.1: If the CMAKE_EXPORT_NO_PACKAGE_REGISTRY <#
variable:CMAKE_EXPORT_NO_PACKAGE_REGISTRY> variable is enabled, the
export(PACKAGE) command will do nothing.
Changed in version 3.15: By default the export(PACKAGE) command does
nothing (see policy CMP0090 <#policy:CMP0090>) because populating the
user package registry has effects outside the source and build trees.
Set the CMAKE_EXPORT_PACKAGE_REGISTRY <#
variable:CMAKE_EXPORT_PACKAGE_REGISTRY> variable to add build
directories to the CMake user package registry.
Configuring Exports
export(SETUP <export-name> [...])
export(SETUP <export-name>
[PACKAGE_DEPENDENCY <dep>
[ENABLED (<bool-true>|<bool-false>|AUTO)]
[EXTRA_ARGS <args>...]
] [...]
[TARGET <target>
[XCFRAMEWORK_LOCATION <location>]
] [...]
)
Added in version 3.29.
Configure the parameters of an export. The arguments are as follows:
PACKAGE_DEPENDENCY <dep>
Note:
Experimental. Gated by
CMAKE_EXPERIMENTAL_EXPORT_PACKAGE_DEPENDENCIES.
Specify a package dependency to configure. This changes how
find_dependency() <#command:find_dependency> calls are written
during export(EXPORT) and install(EXPORT) <#export>. <dep> is
the name of a package to export. This argument accepts the
following additional arguments:
ENABLED
Manually control whether or not the dependency is
exported. This accepts the following values:
<bool-true>
Any value that CMake recognizes as "true". Always
export the dependency, even if no exported targets
depend on it. This can be used to manually add
find_dependency() <#command:find_dependency> calls
to the export.
<bool-false>
Any value that CMake recognizes as "false". Never
export the dependency, even if an exported target
depends on it.
AUTO Only export the dependency if an exported target
depends on it.
EXTRA_ARGS <args>
Specify additional arguments to pass to find_dependency()
<#command:find_dependency> after the REQUIRED argument.
TARGET <target>
Specify a target to configure in this export. This argument
accepts the following additional arguments:
XCFRAMEWORK_LOCATION
Specify the location of an .xcframework which contains
the library from this target. If specified, the generated
code will check to see if the .xcframework exists, and if
it does, it will use the .xcframework as its imported
location instead of the installed library.
fltk_wrap_ui
Create FLTK user interfaces Wrappers.
fltk_wrap_ui(resultingLibraryName source1
source2 ... sourceN )
Produce .h and .cxx files for all the .fl and .fld files listed. The
resulting .h and .cxx files will be added to a variable named
resultingLibraryName_FLTK_UI_SRCS which should be added to your
library.
get_source_file_property
Get a property for a source file.
get_source_file_property(<variable> <file>
[DIRECTORY <dir> | TARGET_DIRECTORY <target>]
<property>)
Gets a property from a source file. The value of the property is
stored in the specified <variable>. If the <file> is not a source
file, or the source property is not found, <variable> will be set to
NOTFOUND. If the source property was defined to be an INHERITED
property (see define_property() <#command:define_property>), the search
will include the relevant parent scopes, as described for the
define_property() <#command:define_property> command.
By default, the source file's property will be read from the current
source directory's scope.
Added in version 3.18: Directory scope can be overridden with one of
the following sub-options:
DIRECTORY <dir>
The source file property will be read from the <dir> directory's
scope. CMake must already know about that source directory,
either by having added it through a call to add_subdirectory()
<#command:add_subdirectory> or <dir> being the top level source
directory. Relative paths are treated as relative to the
current source directory.
TARGET_DIRECTORY <target>
The source file property will be read from the directory scope
in which <target> was created (<target> must therefore already
exist).
Use set_source_files_properties() <#
command:set_source_files_properties> to set property values. Source
file properties usually control how the file is built. One property
that is always there is LOCATION <#prop_sf:LOCATION>.
Note:
The GENERATED <#prop_sf:GENERATED> source file property may be
globally visible. See its documentation for details.
See Also
o define_property() <#command:define_property>
o the more general get_property() <#command:get_property> command
o set_source_files_properties() <#command:set_source_files_properties>
get_target_property
Get a property from a target.
get_target_property(<variable> <target> <property>)
Get a property from a target. The value of the property is stored in
the specified <variable>. If the target property is not found,
<variable> will be set to <variable>-NOTFOUND. If the target property
was defined to be an INHERITED property (see define_property() <#
command:define_property>), the search will include the relevant parent
scopes, as described for the define_property() <#
command:define_property> command.
Use set_target_properties() <#command:set_target_properties> to set
target property values. Properties are usually used to control how a
target is built, but some query the target instead. This command can
get properties for any target so far created. The targets do not need
to be in the current CMakeLists.txt file.
See Also
o define_property() <#command:define_property>
o the more general get_property() <#command:get_property> command
o set_target_properties() <#command:set_target_properties>
o Properties on Targets <#target-properties> for the list of properties
known to CMake
get_test_property
Get a property of the test.
get_test_property(<test> <property> [DIRECTORY <dir>] <variable>)
Get a property from the test. The value of the property is stored in
the specified <variable>. If the <test> is not defined, or the test
property is not found, <variable> will be set to NOTFOUND. If the test
property was defined to be an INHERITED property (see define_property()
<#command:define_property>), the search will include the relevant
parent scopes, as described for the define_property() <#
command:define_property> command.
For a list of standard properties you can type cmake
--help-property-list <#cmdoption-cmake-help-property-list>.
Added in version 3.28: Directory scope can be overridden with the
following sub-option:
DIRECTORY <dir>
The test property will be read from the <dir> directory's scope.
CMake must already know about that source directory, either by
having added it through a call to add_subdirectory() <#
command:add_subdirectory> or <dir> being the top level source
directory. Relative paths are treated as relative to the
current source directory. <dir> may reference a binary
directory.
See Also
o define_property() <#command:define_property>
o the more general get_property() <#command:get_property> command
include_directories
Add include directories to the build.
include_directories([AFTER|BEFORE] [SYSTEM] dir1 [dir2 ...])
Add the given directories to those the compiler uses to search for
include files. Relative paths are interpreted as relative to the
current source directory.
The include directories are added to the INCLUDE_DIRECTORIES <#
prop_dir:INCLUDE_DIRECTORIES> directory property for the current
CMakeLists file. They are also added to the INCLUDE_DIRECTORIES <#
prop_tgt:INCLUDE_DIRECTORIES> target property for each target in the
current CMakeLists file. The target property values are the ones used
by the generators.
By default the directories specified are appended onto the current list
of directories. This default behavior can be changed by setting
CMAKE_INCLUDE_DIRECTORIES_BEFORE <#
variable:CMAKE_INCLUDE_DIRECTORIES_BEFORE> to ON. By using AFTER or
BEFORE explicitly, you can select between appending and prepending,
independent of the default.
If the SYSTEM option is given, the compiler will be told the
directories are meant as system include directories on some platforms.
Signaling this setting might achieve effects such as the compiler
skipping warnings, or these fixed-install system files not being
considered in dependency calculations - see compiler docs.
Arguments to include_directories may use generator expressions with the
syntax $<...>. See the cmake-generator-expressions(7) <#manual:cmake-
generator-expressions(7)> manual for available expressions. See the
cmake-buildsystem(7) <#manual:cmake-buildsystem(7)> manual for more on
defining buildsystem properties.
Note:
Prefer the target_include_directories() <#
command:target_include_directories> command to add include
directories to individual targets and optionally propagate/export
them to dependents.
See Also
o target_include_directories() <#command:target_include_directories>
include_external_msproject
Include an external Microsoft project file in the solution file
produced by Visual Studio Generators <#visual-studio-generators>.
Ignored on other generators.
include_external_msproject(projectname location
[TYPE projectTypeGUID]
[GUID projectGUID]
[PLATFORM platformName]
dep1 dep2 ...)
Includes an external Microsoft project in the generated solution file.
This will create a target named [projectname]. This can be used in the
add_dependencies() <#command:add_dependencies> command to make things
depend on the external project.
TYPE, GUID and PLATFORM are optional parameters that allow one to
specify the type of project, id (GUID) of the project and the name of
the target platform. This is useful for projects requiring values
other than the default (e.g. WIX projects).
Added in version 3.9: If the imported project has different
configuration names than the current project, set the
MAP_IMPORTED_CONFIG_<CONFIG> <#prop_tgt:MAP_IMPORTED_CONFIG_<CONFIG>>
target property to specify the mapping.
include_regular_expression
Set the regular expression used for dependency checking.
include_regular_expression(regex_match [regex_complain])
Sets the regular expressions used in dependency checking. Only files
matching regex_match will be traced as dependencies. Only files
matching regex_complain will generate warnings if they cannot be found
(standard header paths are not searched). The defaults are:
regex_match = "^.*$" (match everything)
regex_complain = "^$" (match empty string only)
install
Specify rules to run at install time.
Synopsis
install(TARGETS <target>... [...])
install(IMPORTED_RUNTIME_ARTIFACTS <target>... [...])
install({FILES | PROGRAMS} <file>... [...])
install(DIRECTORY <dir>... [...])
install(SCRIPT <file> [...])
install(CODE <code> [...])
install(EXPORT <export-name> [...])
install(PACKAGE_INFO <package-name> [...])
install(RUNTIME_DEPENDENCY_SET <set-name> [...])
Introduction
This command generates installation rules for a project. Install rules
specified by calls to the install() command within a source directory
are executed in order during installation.
Changed in version 3.14: Install rules in subdirectories added by calls
to the add_subdirectory() <#command:add_subdirectory> command are
interleaved with those in the parent directory to run in the order
declared (see policy CMP0082 <#policy:CMP0082>).
Changed in version 3.22: The environment variable CMAKE_INSTALL_MODE <#
envvar:CMAKE_INSTALL_MODE> can override the default copying behavior of
install().
Changed in version 3.31: Projects can enable INSTALL_PARALLEL <#
prop_gbl:INSTALL_PARALLEL> to enable a parallel installation. When
using the parallel install, subdirectories added by calls to the
add_subdirectory() <#command:add_subdirectory> command are installed
independently and the order that install rules added in different
subdirectories will run is not guaranteed.
There are multiple signatures for this command. Some of them define
installation options for files and targets. Options common to multiple
signatures are covered here but they are valid only for signatures that
specify them. The common options are:
DESTINATION <dir>
Specify the directory on disk to which a file will be installed.
<dir> should be a relative path. An absolute path is allowed,
but not recommended.
When a relative path is given, it is interpreted relative to the
value of the CMAKE_INSTALL_PREFIX <#
variable:CMAKE_INSTALL_PREFIX> variable. The prefix can be
relocated at install time using the DESTDIR mechanism explained
in the CMAKE_INSTALL_PREFIX <#variable:CMAKE_INSTALL_PREFIX>
variable documentation.
As absolute paths do not work with the cmake --install command's
--prefix <#cmdoption-cmake--install-0> option, or with the cpack
<#manual:cpack(1)> installer generators, it is strongly
recommended to use relative paths throughout for best support by
package maintainers. In particular, there is no need to make
paths absolute by prepending CMAKE_INSTALL_PREFIX <#
variable:CMAKE_INSTALL_PREFIX>; this prefix is used by default
if the DESTINATION is a relative path.
If an absolute path (with a leading slash or drive letter) is
given it is used verbatim.
Changed in version 3.31: <dir> will be normalized according to
the same normalization rules <#normalization> as the
cmake_path() <#command:cmake_path> command.
PERMISSIONS <permission>...
Specify permissions for installed files. Valid permissions are
OWNER_READ, OWNER_WRITE, OWNER_EXECUTE, GROUP_READ, GROUP_WRITE,
GROUP_EXECUTE, WORLD_READ, WORLD_WRITE, WORLD_EXECUTE, SETUID,
and SETGID. Permissions that do not make sense on certain
platforms are ignored on those platforms.
If this option is used multiple times in a single call, its list
of permissions accumulates. If an install(TARGETS) call uses
<artifact-kind> arguments, a separate list of permissions is
accumulated for each kind of artifact.
CONFIGURATIONS <config>...
Specify a list of build configurations for which the install
rule applies (Debug, Release, etc.).
If this option is used multiple times in a single call, its list
of configurations accumulates. If an install(TARGETS) call uses
<artifact-kind> arguments, a separate list of configurations is
accumulated for each kind of artifact.
COMPONENT <component>
Specify an installation component name with which the install
rule is associated, such as Runtime or Development. During
component-specific installation only install rules associated
with the given component name will be executed. During a full
installation all components are installed unless marked with
EXCLUDE_FROM_ALL. If COMPONENT is not provided a default
component "Unspecified" is created. The default component name
may be controlled with the CMAKE_INSTALL_DEFAULT_COMPONENT_NAME
<#variable:CMAKE_INSTALL_DEFAULT_COMPONENT_NAME> variable.
EXCLUDE_FROM_ALL
Added in version 3.6.
Specify that the file is excluded from a full installation and
only installed as part of a component-specific installation
OPTIONAL
Specify that it is not an error if the file to be installed does
not exist.
Added in version 3.1: Command signatures that install files may print
messages during installation. Use the CMAKE_INSTALL_MESSAGE <#
variable:CMAKE_INSTALL_MESSAGE> variable to control which messages are
printed.
Added in version 3.11: Many of the install() variants implicitly create
the directories containing the installed files. If
CMAKE_INSTALL_DEFAULT_DIRECTORY_PERMISSIONS <#
variable:CMAKE_INSTALL_DEFAULT_DIRECTORY_PERMISSIONS> is set, these
directories will be created with the permissions specified. Otherwise,
they will be created according to the uname rules on Unix-like
platforms. Windows platforms are unaffected.
Signatures
install(TARGETS <target>... [...])
Install target Output Artifacts <#output-artifacts> and
associated files:
install(TARGETS <target>... [EXPORT <export-name>]
[RUNTIME_DEPENDENCIES <arg>...|RUNTIME_DEPENDENCY_SET <set-name>]
[<artifact-option>...]
[<artifact-kind> <artifact-option>...]...
[INCLUDES DESTINATION [<dir> ...]]
)
where <artifact-option>... group may contain:
[DESTINATION <dir>]
[PERMISSIONS <permission>...]
[CONFIGURATIONS <config>...]
[COMPONENT <component>]
[NAMELINK_COMPONENT <component>]
[OPTIONAL] [EXCLUDE_FROM_ALL]
[NAMELINK_ONLY|NAMELINK_SKIP]
The first <artifact-option>... group applies to target Output
Artifacts <#output-artifacts> that do not have a dedicated group
specified later in the same call.
Each <artifact-kind> <artifact-option>... group applies to
Output Artifacts <#output-artifacts> of the specified artifact
kind:
ARCHIVE
Target artifacts of this kind include:
o Static libraries (except on macOS when marked as
FRAMEWORK, see below);
o DLL import libraries (on all Windows-based systems
including Cygwin; they have extension .lib, in contrast
to the .dll libraries that go to RUNTIME);
o On AIX, the linker import file created for executables
with ENABLE_EXPORTS <#prop_tgt:ENABLE_EXPORTS> enabled.
o On macOS, the linker import file created for shared
libraries with ENABLE_EXPORTS <#
prop_tgt:ENABLE_EXPORTS> enabled (except when marked as
FRAMEWORK, see below).
LIBRARY
Target artifacts of this kind include:
o Shared libraries, except
o DLLs (these go to RUNTIME, see below),
o on macOS when marked as FRAMEWORK (see below).
RUNTIME
Target artifacts of this kind include:
o Executables (except on macOS when marked as
MACOSX_BUNDLE, see BUNDLE below);
o DLLs (on all Windows-based systems including Cygwin;
note that the accompanying import libraries are of kind
ARCHIVE).
OBJECTS
Added in version 3.9.
Object files associated with object libraries.
FRAMEWORK
Both static and shared libraries marked with the
FRAMEWORK property are treated as FRAMEWORK targets on
macOS.
BUNDLE Executables marked with the MACOSX_BUNDLE <#
prop_tgt:MACOSX_BUNDLE> property are treated as BUNDLE
targets on macOS.
PUBLIC_HEADER
Any PUBLIC_HEADER <#prop_tgt:PUBLIC_HEADER> files
associated with a library are installed in the
destination specified by the PUBLIC_HEADER argument on
non-Apple platforms. Rules defined by this argument are
ignored for FRAMEWORK <#prop_tgt:FRAMEWORK> libraries on
Apple platforms because the associated files are
installed into the appropriate locations inside the
framework folder. See PUBLIC_HEADER <#
prop_tgt:PUBLIC_HEADER> for details.
PRIVATE_HEADER
Similar to PUBLIC_HEADER, but for PRIVATE_HEADER files.
See PRIVATE_HEADER <#prop_tgt:PRIVATE_HEADER> for
details.
RESOURCE
Similar to PUBLIC_HEADER and PRIVATE_HEADER, but for
RESOURCE files. See RESOURCE <#prop_tgt:RESOURCE> for
details.
FILE_SET <set-name>
Added in version 3.23.
File sets are defined by the target_sources(FILE_SET) <#
command:target_sources> command. If the file set
<set-name> exists and is PUBLIC or INTERFACE, any files
in the set are installed under the destination (see
below). The directory structure relative to the file
set's base directories is preserved. For example, a file
added to the file set as /blah/include/myproj/here.h with
a base directory /blah/include would be installed to
myproj/here.h below the destination.
CXX_MODULES_BMI
Added in version 3.28.
Any module files from C++ modules from PUBLIC sources in
a file set of type CXX_MODULES will be installed to the
given DESTINATION. All modules are placed directly in the
destination as no directory structure is derived from the
names of the modules. An empty DESTINATION may be used to
suppress installing these files (for use in generic
code).
For regular executables, static libraries and shared libraries,
the DESTINATION argument is not required. For these target
types, when DESTINATION is omitted, a default destination will
be taken from the appropriate variable from GNUInstallDirs <#
module:GNUInstallDirs>, or set to a built-in default value if
that variable is not defined. The same is true for file sets,
and the public and private headers associated with the installed
targets through the PUBLIC_HEADER <#prop_tgt:PUBLIC_HEADER> and
PRIVATE_HEADER <#prop_tgt:PRIVATE_HEADER> target properties. A
destination must always be provided for module libraries, Apple
bundles and frameworks. A destination can be omitted for
interface and object libraries, but they are handled differently
(see the discussion of this topic toward the end of this
section).
For shared libraries on DLL platforms, if neither RUNTIME nor
ARCHIVE destinations are specified, both the RUNTIME and ARCHIVE
components are installed to their default destinations. If
either a RUNTIME or ARCHIVE destination is specified, the
component is installed to that destination, and the other
component is not installed. If both RUNTIME and ARCHIVE
destinations are specified, then both components are installed
to their respective destinations.
The following table shows the target types with their associated
variables and built-in defaults that apply when no destination
is given:
+---------------+-----------------------------+------------------+
|Target Type | GNUInstallDirs Variable | Built-In Default |
+---------------+-----------------------------+------------------+
|RUNTIME | ${CMAKE_INSTALL_BINDIR} | bin |
+---------------+-----------------------------+------------------+
|LIBRARY | ${CMAKE_INSTALL_LIBDIR} | lib |
+---------------+-----------------------------+------------------+
|ARCHIVE | ${CMAKE_INSTALL_LIBDIR} | lib |
+---------------+-----------------------------+------------------+
|PRIVATE_HEADER | ${CMAKE_INSTALL_INCLUDEDIR} | include |
+---------------+-----------------------------+------------------+
|PUBLIC_HEADER | ${CMAKE_INSTALL_INCLUDEDIR} | include |
+---------------+-----------------------------+------------------+
|FILE_SET (type | ${CMAKE_INSTALL_INCLUDEDIR} | include |
|HEADERS) | | |
+---------------+-----------------------------+------------------+
Projects wishing to follow the common practice of installing
headers into a project-specific subdirectory may prefer using
file sets with appropriate paths and base directories.
Otherwise, they must provide a DESTINATION instead of being able
to rely on the above (see next example below).
To make packages compliant with distribution filesystem layout
policies, if projects must specify a DESTINATION, it is strongly
recommended that they use a path that begins with the
appropriate relative GNUInstallDirs <#module:GNUInstallDirs>
variable. This allows package maintainers to control the
install destination by setting the appropriate cache variables.
The following example shows a static library being installed to
the default destination provided by GNUInstallDirs <#
module:GNUInstallDirs>, but with its headers installed to a
project-specific subdirectory without using file sets:
add_library(mylib STATIC ...)
set_target_properties(mylib PROPERTIES PUBLIC_HEADER mylib.h)
include(GNUInstallDirs)
install(TARGETS mylib
PUBLIC_HEADER
DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/myproj
)
In addition to the common options listed above, each target can
accept the following additional arguments:
NAMELINK_COMPONENT
Added in version 3.12.
On some platforms a versioned shared library has a
symbolic link such as:
lib<name>.so -> lib<name>.so.1
where lib<name>.so.1 is the soname of the library and
lib<name>.so is a "namelink" allowing linkers to find the
library when given -l<name>. The NAMELINK_COMPONENT
option is similar to the COMPONENT option, but it changes
the installation component of a shared library namelink
if one is generated. If not specified, this defaults to
the value of COMPONENT. It is an error to use this
parameter outside of a LIBRARY block.
Changed in version 3.27: This parameter is also usable
for an ARCHIVE block to manage the linker import file
created, on macOS, for shared libraries with
ENABLE_EXPORTS <#prop_tgt:ENABLE_EXPORTS> enabled.
See the Example: Install Targets with Per-Artifact
Components for an example using NAMELINK_COMPONENT.
This option is typically used for package managers that
have separate runtime and development packages. For
example, on Debian systems, the library is expected to be
in the runtime package, and the headers and namelink are
expected to be in the development package.
See the VERSION <#prop_tgt:VERSION> and SOVERSION <#
prop_tgt:SOVERSION> target properties for details on
creating versioned shared libraries.
NAMELINK_ONLY
This option causes the installation of only the namelink
when a library target is installed. On platforms where
versioned shared libraries do not have namelinks or when
a library is not versioned, the NAMELINK_ONLY option
installs nothing. It is an error to use this parameter
outside of a LIBRARY block.
Changed in version 3.27: This parameter is also usable
for an ARCHIVE block to manage the linker import file
created, on macOS, for shared libraries with
ENABLE_EXPORTS <#prop_tgt:ENABLE_EXPORTS> enabled.
When NAMELINK_ONLY is given, either NAMELINK_COMPONENT or
COMPONENT may be used to specify the installation
component of the namelink, but COMPONENT should generally
be preferred.
NAMELINK_SKIP
Similar to NAMELINK_ONLY, but it has the opposite effect:
it causes the installation of library files other than
the namelink when a library target is installed. When
neither NAMELINK_ONLY or NAMELINK_SKIP are given, both
portions are installed. On platforms where versioned
shared libraries do not have symlinks or when a library
is not versioned, NAMELINK_SKIP installs the library. It
is an error to use this parameter outside of a LIBRARY
block.
Changed in version 3.27: This parameter is also usable
for an ARCHIVE block to manage the linker import file
created, on macOS, for shared libraries with
ENABLE_EXPORTS <#prop_tgt:ENABLE_EXPORTS> enabled.
If NAMELINK_SKIP is specified, NAMELINK_COMPONENT has no
effect. It is not recommended to use NAMELINK_SKIP in
conjunction with NAMELINK_COMPONENT.
The install(TARGETS) command can also accept the following
options at the top level:
EXPORT This option associates the installed target files with an
export called <export-name>. It must appear before any
target options. To actually install the export file
itself, call install(EXPORT), documented below. See
documentation of the EXPORT_NAME <#prop_tgt:EXPORT_NAME>
target property to change the name of the exported
target.
If EXPORT is used and the targets include PUBLIC or
INTERFACE file sets, all of them must be specified with
FILE_SET arguments. All PUBLIC or INTERFACE file sets
associated with a target are included in the export.
INCLUDES DESTINATION
This option specifies a list of directories which will be
added to the INTERFACE_INCLUDE_DIRECTORIES <#
prop_tgt:INTERFACE_INCLUDE_DIRECTORIES> target property
of the <targets> when exported by the install(EXPORT)
command. If a relative path is specified, it is treated
as relative to the $<INSTALL_PREFIX> <#
genex:INSTALL_PREFIX>.
Unlike other DESTINATION arguments for the various
install() subcommands, paths given after INCLUDES
DESTINATION are used as given. They are not normalized,
nor assumed to be normalized, although it is recommended
that they are given in normalized form (see Normalization
<#normalization>).
RUNTIME_DEPENDENCY_SET <set-name>
Added in version 3.21.
This option causes all runtime dependencies of installed
executable, shared library, and module targets to be
added to the specified runtime dependency set. This set
can then be installed with an
install(RUNTIME_DEPENDENCY_SET) command.
This keyword and the RUNTIME_DEPENDENCIES keyword are
mutually exclusive.
RUNTIME_DEPENDENCIES <arg>...
Added in version 3.21.
This option causes all runtime dependencies of installed
executable, shared library, and module targets to be
installed along with the targets themselves. The RUNTIME,
LIBRARY, FRAMEWORK, and generic arguments are used to
determine the properties (DESTINATION, COMPONENT, etc.)
of the installation of these dependencies.
RUNTIME_DEPENDENCIES is semantically equivalent to the
following pair of calls:
install(TARGETS ... RUNTIME_DEPENDENCY_SET <set-name>)
install(RUNTIME_DEPENDENCY_SET <set-name> <arg>...)
where <set-name> will be a randomly generated set name.
<arg>... may include any of the following keywords
supported by the install(RUNTIME_DEPENDENCY_SET) command:
o DIRECTORIES
o PRE_INCLUDE_REGEXES
o PRE_EXCLUDE_REGEXES
o POST_INCLUDE_REGEXES
o POST_EXCLUDE_REGEXES
o POST_INCLUDE_FILES
o POST_EXCLUDE_FILES
The RUNTIME_DEPENDENCIES and RUNTIME_DEPENDENCY_SET
keywords are mutually exclusive.
Interface Libraries <#interface-libraries> may be listed among
the targets to install. They install no artifacts but will be
included in an associated EXPORT. If Object Libraries <#object-
libraries> are listed but given no destination for their object
files, they will be exported as Interface Libraries <#interface-
libraries>. This is sufficient to satisfy transitive usage
requirements of other targets that link to the object libraries
in their implementation.
Installing a target with the EXCLUDE_FROM_ALL <#
prop_tgt:EXCLUDE_FROM_ALL> target property set to TRUE has
undefined behavior.
Added in version 3.3: An install destination given as a
DESTINATION argument may use "generator expressions" with the
syntax $<...>. See the cmake-generator-expressions(7) <#
manual:cmake-generator-expressions(7)> manual for available
expressions.
Added in version 3.13: install(TARGETS) can install targets that
were created in other directories. When using such
cross-directory install rules, running make install (or similar)
from a subdirectory will not guarantee that targets from other
directories are up-to-date. You can use target_link_libraries()
<#command:target_link_libraries> or add_dependencies() <#
command:add_dependencies> to ensure that such out-of-directory
targets are built before the subdirectory-specific install rules
are run.
install(IMPORTED_RUNTIME_ARTIFACTS <target>... [...])
Added in version 3.21.
Install runtime artifacts of imported targets:
install(IMPORTED_RUNTIME_ARTIFACTS <target>...
[RUNTIME_DEPENDENCY_SET <set-name>]
[[LIBRARY|RUNTIME|FRAMEWORK|BUNDLE]
[DESTINATION <dir>]
[PERMISSIONS <permission>...]
[CONFIGURATIONS <config>...]
[COMPONENT <component>]
[OPTIONAL] [EXCLUDE_FROM_ALL]
] [...]
)
The IMPORTED_RUNTIME_ARTIFACTS form specifies rules for
installing the runtime artifacts of imported targets. Projects
may do this if they want to bundle outside executables or
modules inside their installation. The LIBRARY, RUNTIME,
FRAMEWORK, and BUNDLE arguments have the same semantics that
they do in the TARGETS mode. Only the runtime artifacts of
imported targets are installed (except in the case of FRAMEWORK
<#prop_tgt:FRAMEWORK> libraries, MACOSX_BUNDLE <#
prop_tgt:MACOSX_BUNDLE> executables, and BUNDLE <#
prop_tgt:BUNDLE> CFBundles.) For example, headers and import
libraries associated with DLLs are not installed. In the case of
FRAMEWORK <#prop_tgt:FRAMEWORK> libraries, MACOSX_BUNDLE <#
prop_tgt:MACOSX_BUNDLE> executables, and BUNDLE <#
prop_tgt:BUNDLE> CFBundles, the entire directory is installed.
The RUNTIME_DEPENDENCY_SET option causes the runtime artifacts
of the imported executable, shared library, and module library
targets to be added to the <set-name> runtime dependency set.
This set can then be installed with an
install(RUNTIME_DEPENDENCY_SET) command.
install(FILES <file>... [...])
install(PROGRAMS <program>... [...])
Note:
If installing header files, consider using file sets defined
by target_sources(FILE_SET) <#command:target_sources>
instead. File sets associate headers with a target and they
install as part of the target.
Install files or programs:
install(<FILES|PROGRAMS> <file>...
TYPE <type> | DESTINATION <dir>
[PERMISSIONS <permission>...]
[CONFIGURATIONS <config>...]
[COMPONENT <component>]
[RENAME <name>] [OPTIONAL] [EXCLUDE_FROM_ALL])
The FILES form specifies rules for installing files for a
project. File names given as relative paths are interpreted
with respect to the current source directory. Files installed
by this form are by default given permissions OWNER_WRITE,
OWNER_READ, GROUP_READ, and WORLD_READ if no PERMISSIONS
argument is given.
The PROGRAMS form is identical to the FILES form except that the
default permissions for the installed file also include
OWNER_EXECUTE, GROUP_EXECUTE, and WORLD_EXECUTE. This form is
intended to install programs that are not targets, such as shell
scripts. Use the TARGETS form to install targets built within
the project.
The list of files... given to FILES or PROGRAMS may use
"generator expressions" with the syntax $<...>. See the
cmake-generator-expressions(7) <#manual:cmake-generator-
expressions(7)> manual for available expressions. However, if
any item begins in a generator expression it must evaluate to a
full path.
The optional RENAME <name> argument is used to specify a name
for the installed file that is different from the original file
name. Renaming is allowed only when a single file is installed
by the command.
Either a TYPE or a DESTINATION must be provided, but not both.
A TYPE argument specifies the generic file type of the files
being installed. A destination will then be set automatically
by taking the corresponding variable from GNUInstallDirs <#
module:GNUInstallDirs>, or by using a built-in default if that
variable is not defined. See the table below for the supported
file types and their corresponding variables and built-in
defaults. Projects can provide a DESTINATION argument instead
of a file type if they wish to explicitly define the install
destination.
+--------------+--------------------------------+---------------------+
|TYPE Argument | GNUInstallDirs Variable | Built-In Default |
+--------------+--------------------------------+---------------------+
|BIN | ${CMAKE_INSTALL_BINDIR} | bin |
+--------------+--------------------------------+---------------------+
|SBIN | ${CMAKE_INSTALL_SBINDIR} | sbin |
+--------------+--------------------------------+---------------------+
|LIB | ${CMAKE_INSTALL_LIBDIR} | lib |
+--------------+--------------------------------+---------------------+
|INCLUDE | ${CMAKE_INSTALL_INCLUDEDIR} | include |
+--------------+--------------------------------+---------------------+
|SYSCONF | ${CMAKE_INSTALL_SYSCONFDIR} | etc |
+--------------+--------------------------------+---------------------+
|SHAREDSTATE | ${CMAKE_INSTALL_SHARESTATEDIR} | com |
+--------------+--------------------------------+---------------------+
|LOCALSTATE | ${CMAKE_INSTALL_LOCALSTATEDIR} | var |
+--------------+--------------------------------+---------------------+
|RUNSTATE | ${CMAKE_INSTALL_RUNSTATEDIR} | <LOCALSTATE |
| | | dir>/run |
+--------------+--------------------------------+---------------------+
|DATA | ${CMAKE_INSTALL_DATADIR} | <DATAROOT dir> |
+--------------+--------------------------------+---------------------+
|INFO | ${CMAKE_INSTALL_INFODIR} | <DATAROOT dir>/info |
+--------------+--------------------------------+---------------------+
|LOCALE | ${CMAKE_INSTALL_LOCALEDIR} | <DATAROOT |
| | | dir>/locale |
+--------------+--------------------------------+---------------------+
|MAN | ${CMAKE_INSTALL_MANDIR} | <DATAROOT dir>/man |
+--------------+--------------------------------+---------------------+
|DOC | ${CMAKE_INSTALL_DOCDIR} | <DATAROOT dir>/doc |
+--------------+--------------------------------+---------------------+
|LIBEXEC | ${CMAKE_INSTALL_LIBEXECDIR} | libexec |
+--------------+--------------------------------+---------------------+
Projects wishing to follow the common practice of installing
headers into a project-specific subdirectory will need to
provide a destination rather than rely on the above. Using file
sets for headers instead of install(FILES) would be even better
(see target_sources(FILE_SET) <#command:target_sources>).
Note that some of the types' built-in defaults use the DATAROOT
directory as a prefix. The DATAROOT prefix is calculated
similarly to the types, with CMAKE_INSTALL_DATAROOTDIR as the
variable and share as the built-in default. You cannot use
DATAROOT as a TYPE parameter; please use DATA instead.
To make packages compliant with distribution filesystem layout
policies, if projects must specify a DESTINATION, it is strongly
recommended that they use a path that begins with the
appropriate relative GNUInstallDirs <#module:GNUInstallDirs>
variable. This allows package maintainers to control the
install destination by setting the appropriate cache variables.
The following example shows how to follow this advice while
installing an image to a project-specific documentation
subdirectory:
include(GNUInstallDirs)
install(FILES logo.png
DESTINATION ${CMAKE_INSTALL_DOCDIR}/myproj
)
Added in version 3.4: An install destination given as a
DESTINATION argument may use "generator expressions" with the
syntax $<...>. See the cmake-generator-expressions(7) <#
manual:cmake-generator-expressions(7)> manual for available
expressions.
Added in version 3.20: An install rename given as a RENAME
argument may use "generator expressions" with the syntax $<...>.
See the cmake-generator-expressions(7) <#manual:cmake-generator-
expressions(7)> manual for available expressions.
Added in version 3.31: The TYPE argument now supports type
LIBEXEC.
install(DIRECTORY <dir>... [...])
Note:
To install a directory sub-tree of headers, consider using
file sets defined by target_sources(FILE_SET) <#
command:target_sources> instead. File sets not only preserve
directory structure, they also associate headers with a
target and install as part of the target.
Install the contents of one or more directories:
install(DIRECTORY dirs...
TYPE <type> | DESTINATION <dir>
[FILE_PERMISSIONS <permission>...]
[DIRECTORY_PERMISSIONS <permission>...]
[USE_SOURCE_PERMISSIONS] [OPTIONAL] [MESSAGE_NEVER]
[CONFIGURATIONS <config>...]
[COMPONENT <component>] [EXCLUDE_FROM_ALL]
[FILES_MATCHING]
[[PATTERN <pattern> | REGEX <regex>]
[EXCLUDE] [PERMISSIONS <permission>...]] [...])
The DIRECTORY form installs contents of one or more directories
to a given destination. The directory structure is copied
verbatim to the destination. The last component of each
directory name is appended to the destination directory but a
trailing slash may be used to avoid this because it leaves the
last component empty. Directory names given as relative paths
are interpreted with respect to the current source directory.
If no input directory names are given the destination directory
will be created but nothing will be installed into it. The
FILE_PERMISSIONS and DIRECTORY_PERMISSIONS options specify
permissions given to files and directories in the destination.
If USE_SOURCE_PERMISSIONS is specified and FILE_PERMISSIONS is
not, file permissions will be copied from the source directory
structure. If no permissions are specified files will be given
the default permissions specified in the FILES form of the
command, and the directories will be given the default
permissions specified in the PROGRAMS form of the command.
Added in version 3.1: The MESSAGE_NEVER option disables file
installation status output.
Installation of directories may be controlled with fine
granularity using the PATTERN or REGEX options. These "match"
options specify a globbing pattern or regular expression to
match directories or files encountered within input directories.
They may be used to apply certain options (see below) to a
subset of the files and directories encountered. The full path
to each input file or directory (with forward slashes) is
matched against the expression. A PATTERN will match only
complete file names: the portion of the full path matching the
pattern must occur at the end of the file name and be preceded
by a slash. A REGEX will match any portion of the full path but
it may use / and $ to simulate the PATTERN behavior. By default
all files and directories are installed whether or not they are
matched. The FILES_MATCHING option may be given before the
first match option to disable installation of files (but not
directories) not matched by any expression. For example, the
code
install(DIRECTORY src/ DESTINATION doc/myproj
FILES_MATCHING PATTERN "*.png")
will extract and install images from a source tree.
Some options may follow a PATTERN or REGEX expression as
described under string(REGEX) <#regex-specification> and are
applied only to files or directories matching them. The EXCLUDE
option will skip the matched file or directory. The PERMISSIONS
option overrides the permissions setting for the matched file or
directory. For example the code
install(DIRECTORY icons scripts/ DESTINATION share/myproj
PATTERN "CVS" EXCLUDE
PATTERN "scripts/*"
PERMISSIONS OWNER_EXECUTE OWNER_WRITE OWNER_READ
GROUP_EXECUTE GROUP_READ)
will install the icons directory to share/myproj/icons and the
scripts directory to share/myproj. The icons will get default
file permissions, the scripts will be given specific
permissions, and any CVS directories will be excluded.
Either a TYPE or a DESTINATION must be provided, but not both.
A TYPE argument specifies the generic file type of the files
within the listed directories being installed. A destination
will then be set automatically by taking the corresponding
variable from GNUInstallDirs <#module:GNUInstallDirs>, or by
using a built-in default if that variable is not defined. See
the table below for the supported file types and their
corresponding variables and built-in defaults. Projects can
provide a DESTINATION argument instead of a file type if they
wish to explicitly define the install destination.
+--------------+--------------------------------+---------------------+
|TYPE Argument | GNUInstallDirs Variable | Built-In Default |
+--------------+--------------------------------+---------------------+
|BIN | ${CMAKE_INSTALL_BINDIR} | bin |
+--------------+--------------------------------+---------------------+
|SBIN | ${CMAKE_INSTALL_SBINDIR} | sbin |
+--------------+--------------------------------+---------------------+
|LIB | ${CMAKE_INSTALL_LIBDIR} | lib |
+--------------+--------------------------------+---------------------+
|INCLUDE | ${CMAKE_INSTALL_INCLUDEDIR} | include |
+--------------+--------------------------------+---------------------+
|SYSCONF | ${CMAKE_INSTALL_SYSCONFDIR} | etc |
+--------------+--------------------------------+---------------------+
|SHAREDSTATE | ${CMAKE_INSTALL_SHARESTATEDIR} | com |
+--------------+--------------------------------+---------------------+
|LOCALSTATE | ${CMAKE_INSTALL_LOCALSTATEDIR} | var |
+--------------+--------------------------------+---------------------+
|RUNSTATE | ${CMAKE_INSTALL_RUNSTATEDIR} | <LOCALSTATE |
| | | dir>/run |
+--------------+--------------------------------+---------------------+
|DATA | ${CMAKE_INSTALL_DATADIR} | <DATAROOT dir> |
+--------------+--------------------------------+---------------------+
|INFO | ${CMAKE_INSTALL_INFODIR} | <DATAROOT dir>/info |
+--------------+--------------------------------+---------------------+
|LOCALE | ${CMAKE_INSTALL_LOCALEDIR} | <DATAROOT |
| | | dir>/locale |
+--------------+--------------------------------+---------------------+
|MAN | ${CMAKE_INSTALL_MANDIR} | <DATAROOT dir>/man |
+--------------+--------------------------------+---------------------+
|DOC | ${CMAKE_INSTALL_DOCDIR} | <DATAROOT dir>/doc |
+--------------+--------------------------------+---------------------+
|LIBEXEC | ${CMAKE_INSTALL_LIBEXECDIR} | libexec |
+--------------+--------------------------------+---------------------+
Note that some of the types' built-in defaults use the DATAROOT
directory as a prefix. The DATAROOT prefix is calculated
similarly to the types, with CMAKE_INSTALL_DATAROOTDIR as the
variable and share as the built-in default. You cannot use
DATAROOT as a TYPE parameter; please use DATA instead.
To make packages compliant with distribution filesystem layout
policies, if projects must specify a DESTINATION, it is strongly
recommended that they use a path that begins with the
appropriate relative GNUInstallDirs <#module:GNUInstallDirs>
variable. This allows package maintainers to control the
install destination by setting the appropriate cache variables.
Added in version 3.4: An install destination given as a
DESTINATION argument may use "generator expressions" with the
syntax $<...>. See the cmake-generator-expressions(7) <#
manual:cmake-generator-expressions(7)> manual for available
expressions.
Added in version 3.5: The list of dirs... given to DIRECTORY may
use "generator expressions" too.
Added in version 3.31: The TYPE argument now supports type
LIBEXEC.
install(SCRIPT <file> [...])
install(CODE <code> [...])
Invoke CMake scripts or code during installation:
install([[SCRIPT <file>] [CODE <code>]]
[ALL_COMPONENTS | COMPONENT <component>]
[EXCLUDE_FROM_ALL] [...])
The SCRIPT form will invoke the given CMake script files during
installation. If the script file name is a relative path it
will be interpreted with respect to the current source
directory. The CODE form will invoke the given CMake code
during installation. Code is specified as a single argument
inside a double-quoted string. For example, the code
install(CODE "MESSAGE(\"Sample install message.\")")
will print a message during installation.
Added in version 3.21: When the ALL_COMPONENTS option is given,
the custom installation script code will be executed for every
component of a component-specific installation. This option is
mutually exclusive with the COMPONENT option.
Added in version 3.14: <file> or <code> may use "generator
expressions" with the syntax $<...> (in the case of <file>, this
refers to their use in the file name, not the file's contents).
See the cmake-generator-expressions(7) <#manual:cmake-generator-
expressions(7)> manual for available expressions.
install(EXPORT <export-name> [...])
Install a CMake file exporting targets for dependent projects:
install(EXPORT <export-name> DESTINATION <dir>
[NAMESPACE <namespace>] [FILE <name>.cmake]
[PERMISSIONS <permission>...]
[CONFIGURATIONS <config>...]
[CXX_MODULES_DIRECTORY <directory>]
[EXPORT_LINK_INTERFACE_LIBRARIES]
[COMPONENT <component>]
[EXCLUDE_FROM_ALL]
[EXPORT_PACKAGE_DEPENDENCIES])
install(EXPORT_ANDROID_MK <export-name> DESTINATION <dir> [...])
The EXPORT form generates and installs a CMake file containing
code to import targets from the installation tree into another
project. Target installations are associated with the export
<export-name> using the EXPORT option of the install(TARGETS)
signature documented above. The NAMESPACE option will prepend
<namespace> to the target names as they are written to the
import file. By default the generated file will be called
<export-name>.cmake but the FILE option may be used to specify a
different name. The value given to the FILE option must be a
file name with the .cmake extension.
If a CONFIGURATIONS option is given then the file will only be
installed when one of the named configurations is installed.
Additionally, the generated import file will reference only the
matching target configurations. See the
CMAKE_MAP_IMPORTED_CONFIG_<CONFIG> <#
variable:CMAKE_MAP_IMPORTED_CONFIG_<CONFIG>> variable to map
configurations of dependent projects to the installed
configurations. The EXPORT_LINK_INTERFACE_LIBRARIES keyword, if
present, causes the contents of the properties matching
(IMPORTED_)?LINK_INTERFACE_LIBRARIES(_<CONFIG>)? to be exported,
when policy CMP0022 <#policy:CMP0022> is NEW.
Note:
The installed <export-name>.cmake file may come with
additional per-configuration <export-name>-*.cmake files to
be loaded by globbing. Do not use an export name that is the
same as the package name in combination with installing a
<package-name>-config.cmake file or the latter may be
incorrectly matched by the glob and loaded.
When a COMPONENT option is given, the listed <component>
implicitly depends on all components mentioned in the export
set. The exported <name>.cmake file will require each of the
exported components to be present in order for dependent
projects to build properly. For example, a project may define
components Runtime and Development, with shared libraries going
into the Runtime component and static libraries and headers
going into the Development component. The export set would also
typically be part of the Development component, but it would
export targets from both the Runtime and Development components.
Therefore, the Runtime component would need to be installed if
the Development component was installed, but not vice versa. If
the Development component was installed without the Runtime
component, dependent projects that try to link against it would
have build errors. Package managers, such as APT and RPM,
typically handle this by listing the Runtime component as a
dependency of the Development component in the package metadata,
ensuring that the library is always installed if the headers and
CMake export file are present.
Added in version 3.7: In addition to cmake language files, the
EXPORT_ANDROID_MK mode may be used to specify an export to the
android ndk build system. This mode accepts the same options as
the normal export mode. The Android NDK supports the use of
prebuilt libraries, both static and shared. This allows cmake to
build the libraries of a project and make them available to an
ndk build system complete with transitive dependencies, include
flags and defines required to use the libraries.
CXX_MODULES_DIRECTORY
Added in version 3.28.
Specify a subdirectory to store C++ module information
for targets in the export set. This directory will be
populated with files which add the necessary target
property information to the relevant targets. Note that
without this information, none of the C++ modules which
are part of the targets in the export set will support
being imported in consuming targets.
EXPORT_PACKAGE_DEPENDENCIES
Note:
Experimental. Gated by
CMAKE_EXPERIMENTAL_EXPORT_PACKAGE_DEPENDENCIES.
Specify that find_dependency() <#command:find_dependency>
calls should be exported. If this argument is specified,
CMake examines all targets in the export set and gathers
their INTERFACE link targets. If any such targets either
were found with find_package() <#command:find_package> or
have the EXPORT_FIND_PACKAGE_NAME <#
prop_tgt:EXPORT_FIND_PACKAGE_NAME> property set, and such
package dependency was not disabled by passing ENABLED
OFF to export(SETUP) <#setup>, then a find_dependency()
<#command:find_dependency> call is written with the
target's corresponding package name, a REQUIRED argument,
and any additional arguments specified by the EXTRA_ARGS
argument of export(SETUP) <#setup>. Any package
dependencies that were manually specified by passing
ENABLED ON to export(SETUP) <#setup> are also added, even
if the exported targets don't depend on any targets from
them.
The find_dependency() <#command:find_dependency> calls
are written in the following order:
1. Any package dependencies that were listed in
export(SETUP) <#setup> are written in the order they
were first specified, regardless of whether or not
they contain INTERFACE dependencies of the exported
targets.
2. Any package dependencies that contain INTERFACE link
dependencies of the exported targets and that were
never specified in export(SETUP) <#setup> are written
in the order they were first found.
The EXPORT form is useful to help outside projects use targets
built and installed by the current project. For example, the
code
install(TARGETS myexe EXPORT myproj DESTINATION bin)
install(EXPORT myproj NAMESPACE mp_ DESTINATION lib/myproj)
install(EXPORT_ANDROID_MK myproj DESTINATION share/ndk-modules)
will install the executable myexe to <prefix>/bin and code to
import it in the file <prefix>/lib/myproj/myproj.cmake and
<prefix>/share/ndk-modules/Android.mk. An outside project may
load this file with the include command and reference the myexe
executable from the installation tree using the imported target
name mp_myexe as if the target were built in its own tree.
install(PACKAGE_INFO <package-name> [...])
Added in version 3.31.
Note:
Experimental. Gated by
CMAKE_EXPERIMENTAL_EXPORT_PACKAGE_INFO.
Installs a Common Package Specification <https://cps-org.github
.io/cps/> file exporting targets for dependent projects:
install(PACKAGE_INFO <package-name> EXPORT <export-name>
[APPENDIX <appendix-name>]
[DESTINATION <dir>]
[LOWER_CASE_FILE]
[VERSION <version>
[COMPAT_VERSION <version>]
[VERSION_SCHEMA <string>]]
[DEFAULT_TARGETS <target>...]
[DEFAULT_CONFIGURATIONS <config>...]
[PERMISSIONS <permission>...]
[CONFIGURATIONS <config>...]
[COMPONENT <component>]
[EXCLUDE_FROM_ALL])
The PACKAGE_INFO form generates and installs a Common Package
Specification file which describes installed targets such that
they can be consumed by another project. Target installations
are associated with the export <export-name> using the EXPORT
option of the install(TARGETS) signature documented above.
Unlike install(EXPORT), this information is not expressed in
CMake code, and can be consumed by tools other than CMake. When
imported into another CMake project, the imported targets will
be prefixed with <package-name>::. By default, the generated
file will be called <package-name>[-<appendix-name>].cps. If
LOWER_CASE_FILE is given, the package name as it appears on disk
(in both the file name and install destination) will be first
converted to lower case.
If DESTINATION is not specified, a platform-specific default is
used.
If APPENDIX is specified, rather than generating a top level
package specification, the specified targets will be exported as
an appendix to the named package. Appendices may be used to
separate less commonly used targets (along with their external
dependencies) from the rest of a package. This enables
consumers to ignore transitive dependencies for targets that
they don't use, and also allows a single logical "package" to be
composed of artifacts produced by multiple build trees.
Appendices are not permitted to change basic package metadata;
therefore, none of VERSION, COMPAT_VERSION, VERSION_SCHEMA,
DEFAULT_TARGETS or DEFAULT_CONFIGURATIONS may be specified in
combination with APPENDIX. Additionally, it is strongly
recommended that use of LOWER_CASE_FILE should be consistent
between the main package and any appendices.
install(RUNTIME_DEPENDENCY_SET <set-name> [...])
Added in version 3.21.
Installs a runtime dependency set:
install(RUNTIME_DEPENDENCY_SET <set-name>
[[LIBRARY|RUNTIME|FRAMEWORK]
[DESTINATION <dir>]
[PERMISSIONS <permission>...]
[CONFIGURATIONS <config>...]
[COMPONENT <component>]
[NAMELINK_COMPONENT <component>]
[OPTIONAL] [EXCLUDE_FROM_ALL]
] [...]
[PRE_INCLUDE_REGEXES <regex>...]
[PRE_EXCLUDE_REGEXES <regex>...]
[POST_INCLUDE_REGEXES <regex>...]
[POST_EXCLUDE_REGEXES <regex>...]
[POST_INCLUDE_FILES <file>...]
[POST_EXCLUDE_FILES <file>...]
[DIRECTORIES <dir>...]
)
Installs a runtime dependency set previously created by one or
more install(TARGETS) or install(IMPORTED_RUNTIME_ARTIFACTS)
commands. The dependencies of targets belonging to a runtime
dependency set are installed in the RUNTIME destination and
component on DLL platforms, and in the LIBRARY destination and
component on non-DLL platforms. macOS frameworks are installed
in the FRAMEWORK destination and component. Targets built
within the build tree will never be installed as runtime
dependencies, nor will their own dependencies, unless the
targets themselves are installed with install(TARGETS).
The generated install script calls
file(GET_RUNTIME_DEPENDENCIES) <#get-runtime-dependencies> on
the build-tree files to calculate the runtime dependencies. The
build-tree executable files are passed as the EXECUTABLES
argument, the build-tree shared libraries as the LIBRARIES
argument, and the build-tree modules as the MODULES argument. On
macOS, if one of the executables is a MACOSX_BUNDLE <#
prop_tgt:MACOSX_BUNDLE>, that executable is passed as the
BUNDLE_EXECUTABLE argument. At most one such bundle executable
may be in the runtime dependency set on macOS. The MACOSX_BUNDLE
<#prop_tgt:MACOSX_BUNDLE> property has no effect on other
platforms. Note that file(GET_RUNTIME_DEPENDENCIES) <#get-
runtime-dependencies> only supports collecting the runtime
dependencies for Windows, Linux and macOS platforms, so
install(RUNTIME_DEPENDENCY_SET) has the same limitation.
The following sub-arguments are forwarded through as the
corresponding arguments to file(GET_RUNTIME_DEPENDENCIES) <#get-
runtime-dependencies> (for those that provide a non-empty list
of directories, regular expressions or files). They all support
generator expressions <#manual:cmake-generator-expressions(7)>.
o DIRECTORIES <dir>...
o PRE_INCLUDE_REGEXES <regex>...
o PRE_EXCLUDE_REGEXES <regex>...
o POST_INCLUDE_REGEXES <regex>...
o POST_EXCLUDE_REGEXES <regex>...
o POST_INCLUDE_FILES <file>...
o POST_EXCLUDE_FILES <file>...
Note:
This command supersedes the install_targets() <#
command:install_targets> command and the PRE_INSTALL_SCRIPT <#
prop_tgt:PRE_INSTALL_SCRIPT> and POST_INSTALL_SCRIPT <#
prop_tgt:POST_INSTALL_SCRIPT> target properties. It also replaces
the FILES forms of the install_files() <#command:install_files> and
install_programs() <#command:install_programs> commands. The
processing order of these install rules relative to those generated
by install_targets() <#command:install_targets>, install_files() <#
command:install_files>, and install_programs() <#
command:install_programs> commands is not defined.
Examples
Example: Install Targets with Per-Artifact Components
Consider a project that defines targets with different artifact kinds:
add_executable(myExe myExe.c)
add_library(myStaticLib STATIC myStaticLib.c)
target_sources(myStaticLib PUBLIC FILE_SET HEADERS FILES myStaticLib.h)
add_library(mySharedLib SHARED mySharedLib.c)
target_sources(mySharedLib PUBLIC FILE_SET HEADERS FILES mySharedLib.h)
set_property(TARGET mySharedLib PROPERTY SOVERSION 1)
We may call install(TARGETS) with <artifact-kind> arguments to specify
different options for each kind of artifact:
install(TARGETS
myExe
mySharedLib
myStaticLib
RUNTIME # Following options apply to runtime artifacts.
COMPONENT Runtime
LIBRARY # Following options apply to library artifacts.
COMPONENT Runtime
NAMELINK_COMPONENT Development
ARCHIVE # Following options apply to archive artifacts.
COMPONENT Development
DESTINATION lib/static
FILE_SET HEADERS # Following options apply to file set HEADERS.
COMPONENT Development
)
This will:
o Install myExe to <prefix>/bin, the default RUNTIME artifact
destination, as part of the Runtime component.
o On non-DLL platforms:
o Install libmySharedLib.so.1 to <prefix>/lib, the default LIBRARY
artifact destination, as part of the Runtime component.
o Install the libmySharedLib.so "namelink" (symbolic link) to
<prefix>/lib, the default LIBRARY artifact destination, as part of
the Development component.
o On DLL platforms:
o Install mySharedLib.dll to <prefix>/bin, the default RUNTIME
artifact destination, as part of the Runtime component.
o Install mySharedLib.lib to <prefix>/lib/static, the specified
ARCHIVE artifact destination, as part of the Development component.
o Install myStaticLib to <prefix>/lib/static, the specified ARCHIVE
artifact destination, as part of the Development component.
o Install mySharedLib.h and myStaticLib.h to <prefix>/include, the
default destination for a file set of type HEADERS, as part of the
Development component.
Example: Install Targets to Per-Config Destinations
Each install(TARGETS) call installs a given target output artifact <#
output-artifacts> to at most one DESTINATION, but the install rule
itself may be filtered by the CONFIGURATIONS option. In order to
install to a different destination for each configuration, one call per
configuration is needed. For example, the code:
install(TARGETS myExe
CONFIGURATIONS Debug
RUNTIME
DESTINATION Debug/bin
)
install(TARGETS myExe
CONFIGURATIONS Release
RUNTIME
DESTINATION Release/bin
)
will install myExe to <prefix>/Debug/bin in the Debug configuration,
and to <prefix>/Release/bin in the Release configuration.
Generated Installation Script
Note:
Use of this feature is not recommended. Please consider using the
cmake --install <#cmdoption-cmake-install> instead.
The install() command generates a file, cmake_install.cmake, inside the
build directory, which is used internally by the generated install
target and by CPack. You can also invoke this script manually with
cmake -P <#cmdoption-cmake-P>. This script accepts several variables:
COMPONENT
Set this variable to install only a single CPack component as
opposed to all of them. For example, if you only want to install
the Development component, run cmake -DCOMPONENT=Development -P
cmake_install.cmake.
BUILD_TYPE
Set this variable to change the build type if you are using a
multi-config generator. For example, to install with the Debug
configuration, run cmake -DBUILD_TYPE=Debug -P
cmake_install.cmake.
DESTDIR
This is an environment variable rather than a CMake variable. It
allows you to change the installation prefix on UNIX systems.
See DESTDIR <#envvar:DESTDIR> for details.
link_directories
Add directories in which the linker will look for libraries.
link_directories([AFTER|BEFORE] directory1 [directory2 ...])
Adds the paths in which the linker should search for libraries.
Relative paths given to this command are interpreted as relative to the
current source directory, see CMP0015 <#policy:CMP0015>.
The command will apply only to targets created after it is called.
Added in version 3.13: The directories are added to the
LINK_DIRECTORIES <#prop_dir:LINK_DIRECTORIES> directory property for
the current CMakeLists.txt file, converting relative paths to absolute
as needed. See the cmake-buildsystem(7) <#manual:cmake-buildsystem(7)>
manual for more on defining buildsystem properties.
Added in version 3.13: By default the directories specified are
appended onto the current list of directories. This default behavior
can be changed by setting CMAKE_LINK_DIRECTORIES_BEFORE <#
variable:CMAKE_LINK_DIRECTORIES_BEFORE> to ON. By using AFTER or
BEFORE explicitly, you can select between appending and prepending,
independent of the default.
Added in version 3.13: Arguments to link_directories may use "generator
expressions" with the syntax "$<...>". See the
cmake-generator-expressions(7) <#manual:cmake-generator-expressions(7)>
manual for available expressions.
Note:
This command is rarely necessary and should be avoided where there
are other choices. Prefer to pass full absolute paths to libraries
where possible, since this ensures the correct library will always
be linked. The find_library() <#command:find_library> command
provides the full path, which can generally be used directly in
calls to target_link_libraries() <#command:target_link_libraries>.
Situations where a library search path may be needed include:
o Project generators like Xcode where the user can switch target
architecture at build time, but a full path to a library cannot be
used because it only provides one architecture (i.e. it is not a
universal binary).
o Libraries may themselves have other private library dependencies
that expect to be found via RPATH mechanisms, but some linkers are
not able to fully decode those paths (e.g. due to the presence of
things like $ORIGIN).
If a library search path must be provided, prefer to localize the
effect where possible by using the target_link_directories() <#
command:target_link_directories> command rather than
link_directories(). The target-specific command can also control
how the search directories propagate to other dependent targets.
See Also
o target_link_directories() <#command:target_link_directories>
o target_link_libraries() <#command:target_link_libraries>
link_libraries
Link libraries to all targets added later.
link_libraries([item1 [item2 [...]]]
[[debug|optimized|general] <item>] ...)
Specify libraries or flags to use when linking any targets created
later in the current directory or below by commands such as
add_executable() <#command:add_executable> or add_library() <#
command:add_library>. See the target_link_libraries() <#
command:target_link_libraries> command for meaning of arguments.
Note:
The target_link_libraries() <#command:target_link_libraries> command
should be preferred whenever possible. Library dependencies are
chained automatically, so directory-wide specification of link
libraries is rarely needed.
load_cache
Load in the values from another project's CMake cache.
load_cache(pathToBuildDirectory READ_WITH_PREFIX prefix entry1...)
Reads the cache and store the requested entries in variables with their
name prefixed with the given prefix. This only reads the values, and
does not create entries in the local project's cache.
load_cache(pathToBuildDirectory [EXCLUDE entry1...]
[INCLUDE_INTERNALS entry1...])
Loads in the values from another cache and store them in the local
project's cache as internal entries. This is useful for a project that
depends on another project built in a different tree. EXCLUDE option
can be used to provide a list of entries to be excluded.
INCLUDE_INTERNALS can be used to provide a list of internal entries to
be included. Normally, no internal entries are brought in. Use of
this form of the command is strongly discouraged, but it is provided
for backward compatibility.
project
Set the name of the project.
Synopsis
project(<PROJECT-NAME> [<language-name>...])
project(<PROJECT-NAME>
[VERSION <major>[.<minor>[.<patch>[.<tweak>]]]]
[DESCRIPTION <project-description-string>]
[HOMEPAGE_URL <url-string>]
[LANGUAGES <language-name>...])
Sets the name of the project, and stores it in the variable
PROJECT_NAME <#variable:PROJECT_NAME>. When called from the top-level
CMakeLists.txt also stores the project name in the variable
CMAKE_PROJECT_NAME <#variable:CMAKE_PROJECT_NAME>.
Also sets the variables:
PROJECT_SOURCE_DIR <#variable:PROJECT_SOURCE_DIR>,
<PROJECT-NAME>_SOURCE_DIR <#variable:<PROJECT-NAME>_SOURCE_DIR>
Absolute path to the source directory for the project.
PROJECT_BINARY_DIR <#variable:PROJECT_BINARY_DIR>,
<PROJECT-NAME>_BINARY_DIR <#variable:<PROJECT-NAME>_BINARY_DIR>
Absolute path to the binary directory for the project.
PROJECT_IS_TOP_LEVEL <#variable:PROJECT_IS_TOP_LEVEL>,
<PROJECT-NAME>_IS_TOP_LEVEL <#variable:<PROJECT-NAME>_IS_TOP_LEVEL>
Added in version 3.21.
Boolean value indicating whether the project is top-level.
Further variables are set by the optional arguments described in
Options further below. Where an option is not given, its corresponding
variable is set to the empty string.
Note that variables of the form <name>_SOURCE_DIR and <name>_BINARY_DIR
may also be set by other commands before project() is called (see the
FetchContent_MakeAvailable() <#command:fetchcontent_makeavailable>
command for one example). Projects should not rely on
<PROJECT-NAME>_SOURCE_DIR or <PROJECT-NAME>_BINARY_DIR holding a
particular value outside of the scope of the call to project() or one
of its child scopes.
Changed in version 3.30: <PROJECT-NAME>_SOURCE_DIR,
<PROJECT-NAME>_BINARY_DIR, and <PROJECT-NAME>_IS_TOP_LEVEL, if already
set as normal variables when project(<PROJECT-NAME> ...) is called, are
updated by the call. Cache entries by the same names are always set as
before. See release notes for 3.30.3, 3.30.4, and 3.30.5 for details.
Changed in version 3.31: <PROJECT-NAME>_SOURCE_DIR,
<PROJECT-NAME>_BINARY_DIR, and <PROJECT-NAME>_IS_TOP_LEVEL are always
set as normal variables by project(<PROJECT-NAME> ...). See policy
CMP0180 <#policy:CMP0180>. Cache entries by the same names are always
set as before.
Options
The options are:
VERSION <version>
Optional; may not be used unless policy CMP0048 <#
policy:CMP0048> is set to NEW.
Takes a <version> argument composed of non-negative integer
components, i.e. <major>[.<minor>[.<patch>[.<tweak>]]], and sets
the variables
o PROJECT_VERSION <#variable:PROJECT_VERSION>,
<PROJECT-NAME>_VERSION <#variable:<PROJECT-NAME>_VERSION>
o PROJECT_VERSION_MAJOR <#variable:PROJECT_VERSION_MAJOR>,
<PROJECT-NAME>_VERSION_MAJOR <#variable:<PROJECT-
NAME>_VERSION_MAJOR>
o PROJECT_VERSION_MINOR <#variable:PROJECT_VERSION_MINOR>,
<PROJECT-NAME>_VERSION_MINOR <#variable:<PROJECT-
NAME>_VERSION_MINOR>
o PROJECT_VERSION_PATCH <#variable:PROJECT_VERSION_PATCH>,
<PROJECT-NAME>_VERSION_PATCH <#variable:<PROJECT-
NAME>_VERSION_PATCH>
o PROJECT_VERSION_TWEAK <#variable:PROJECT_VERSION_TWEAK>,
<PROJECT-NAME>_VERSION_TWEAK <#variable:<PROJECT-
NAME>_VERSION_TWEAK>.
Added in version 3.12: When the project() command is called from
the top-level CMakeLists.txt, then the version is also stored in
the variable CMAKE_PROJECT_VERSION <#
variable:CMAKE_PROJECT_VERSION>.
DESCRIPTION <project-description-string>
Added in version 3.9.
Optional. Sets the variables
o PROJECT_DESCRIPTION <#variable:PROJECT_DESCRIPTION>,
<PROJECT-NAME>_DESCRIPTION <#variable:<PROJECT-
NAME>_DESCRIPTION>
to <project-description-string>. It is recommended that this
description is a relatively short string, usually no more than a
few words.
When the project() command is called from the top-level
CMakeLists.txt, then the description is also stored in the
variable CMAKE_PROJECT_DESCRIPTION <#
variable:CMAKE_PROJECT_DESCRIPTION>.
Added in version 3.12: Added the <PROJECT-NAME>_DESCRIPTION
variable.
HOMEPAGE_URL <url-string>
Added in version 3.12.
Optional. Sets the variables
o PROJECT_HOMEPAGE_URL <#variable:PROJECT_HOMEPAGE_URL>,
<PROJECT-NAME>_HOMEPAGE_URL <#variable:<PROJECT-
NAME>_HOMEPAGE_URL>
to <url-string>, which should be the canonical home URL for the
project.
When the project() command is called from the top-level
CMakeLists.txt, then the URL also is stored in the variable
CMAKE_PROJECT_HOMEPAGE_URL <#
variable:CMAKE_PROJECT_HOMEPAGE_URL>.
LANGUAGES <language-name>...
Optional. Can also be specified without LANGUAGES keyword per
the first, short signature.
Selects which programming languages are needed to build the
project.
Supported languages are C, CXX (i.e. C++), CSharp (i.e. C#), CUDA,
OBJC (i.e. Objective-C), OBJCXX (i.e. Objective-C++), Fortran, HIP,
ISPC, Swift, ASM, ASM_NASM, ASM_MARMASM, ASM_MASM, and ASM-ATT.
Added in version 3.8: Added CSharp and CUDA support.
Added in version 3.15: Added Swift support.
Added in version 3.16: Added OBJC and OBJCXX support.
Added in version 3.18: Added ISPC support.
Added in version 3.21: Added HIP support.
Added in version 3.26: Added ASM_MARMASM support.
If enabling ASM, list it last so that CMake can check whether compilers
for other languages like C work for assembly too.
By default C and CXX are enabled if no language options are given.
Specify language NONE, or use the LANGUAGES keyword and list no
languages, to skip enabling any languages.
The variables set through the VERSION, DESCRIPTION and HOMEPAGE_URL
options are intended for use as default values in package metadata and
documentation.
Code Injection
A number of variables can be defined by the user to specify files to
include at different points during the execution of the project()
command. The following outlines the steps performed during a project()
call:
o Added in version 3.15: For every project() call regardless of the
project name, include the file(s) and module(s) named by
CMAKE_PROJECT_INCLUDE_BEFORE <#
variable:CMAKE_PROJECT_INCLUDE_BEFORE>, if set.
o Added in version 3.17: If the project() command specifies
<PROJECT-NAME> as its project name, include the file(s) and module(s)
named by CMAKE_PROJECT_<PROJECT-NAME>_INCLUDE_BEFORE <#
variable:CMAKE_PROJECT_<PROJECT-NAME>_INCLUDE_BEFORE>, if set.
o Set the various project-specific variables detailed in the Synopsis
and Options sections above.
o For the very first project() call only:
o If CMAKE_TOOLCHAIN_FILE <#variable:CMAKE_TOOLCHAIN_FILE> is set,
read it at least once. It may be read multiple times and it may
also be read again when enabling languages later (see below).
o Set the variables describing the host and target platforms.
Language-specific variables might or might not be set at this
point. On the first run, the only language-specific variables that
might be defined are those a toolchain file may have set. On
subsequent runs, language-specific variables cached from a previous
run may be set.
o Added in version 3.24: Include each file listed in
CMAKE_PROJECT_TOP_LEVEL_INCLUDES <#
variable:CMAKE_PROJECT_TOP_LEVEL_INCLUDES>, if set. The variable is
ignored by CMake thereafter.
o Enable any languages specified in the call, or the default languages
if none were provided. The toolchain file may be re-read when
enabling a language for the first time.
o Added in version 3.15: For every project() call regardless of the
project name, include the file(s) and module(s) named by
CMAKE_PROJECT_INCLUDE <#variable:CMAKE_PROJECT_INCLUDE>, if set.
o If the project() command specifies <PROJECT-NAME> as its project
name, include the file(s) and module(s) named by
CMAKE_PROJECT_<PROJECT-NAME>_INCLUDE <#
variable:CMAKE_PROJECT_<PROJECT-NAME>_INCLUDE>, if set.
Usage
The top-level CMakeLists.txt file for a project must contain a literal,
direct call to the project() command; loading one through the include()
<#command:include> command is not sufficient. If no such call exists,
CMake will issue a warning and pretend there is a project(Project) at
the top to enable the default languages (C and CXX).
Note:
Call the project() command near the top of the top-level
CMakeLists.txt, but after calling cmake_minimum_required() <#
command:cmake_minimum_required>. It is important to establish
version and policy settings before invoking other commands whose
behavior they may affect and for this reason the project() command
will issue a warning if this order is not kept. See also policy
CMP0000 <#policy:CMP0000>.
remove_definitions
Remove -D define flags added by add_definitions() <#
command:add_definitions>.
remove_definitions(-DFOO -DBAR ...)
Removes flags (added by add_definitions() <#command:add_definitions>)
from the compiler command line for sources in the current directory and
below.
set_source_files_properties
Source files can have properties that affect how they are built.
set_source_files_properties(<files> ...
[DIRECTORY <dirs> ...]
[TARGET_DIRECTORY <targets> ...]
PROPERTIES <prop1> <value1>
[<prop2> <value2>] ...)
Sets properties associated with source files using a key/value paired
list.
Added in version 3.18: By default, source file properties are only
visible to targets added in the same directory (CMakeLists.txt).
Visibility can be set in other directory scopes using one or both of
the following options:
DIRECTORY <dirs>...
The source file properties will be set in each of the <dirs>
directories' scopes. CMake must already know about each of
these source directories, either by having added them through a
call to add_subdirectory() <#command:add_subdirectory> or it
being the top level source directory. Relative paths are
treated as relative to the current source directory.
TARGET_DIRECTORY <targets>...
The source file properties will be set in each of the directory
scopes where any of the specified <targets> were created (the
<targets> must therefore already exist).
Use get_source_file_property() <#command:get_source_file_property> to
get property values. See also the set_property(SOURCE) <#
command:set_property> command.
Note:
The GENERATED <#prop_sf:GENERATED> source file property may be
globally visible. See its documentation for details.
See Also
o define_property() <#command:define_property>
o get_source_file_property() <#command:get_source_file_property>
o Properties on Source Files <#source-file-properties> for the list of
properties known to CMake
set_target_properties
Targets can have properties that affect how they are built.
set_target_properties(<targets> ...
PROPERTIES <prop1> <value1>
[<prop2> <value2>] ...)
Sets properties on targets. The syntax for the command is to list all
the targets you want to change, and then provide the values you want to
set next. You can use any prop value pair you want and extract it
later with the get_property() <#command:get_property> or
get_target_property() <#command:get_target_property> command.
Alias Targets <#alias-targets> do not support setting target
properties.
See Also
o define_property() <#command:define_property>
o get_target_property() <#command:get_target_property>
o the more general set_property() <#command:set_property> command
o Properties on Targets <#target-properties> for the list of properties
known to CMake
set_tests_properties
Set a property of the tests.
set_tests_properties(<tests>...
[DIRECTORY <dir>]
PROPERTIES <prop1> <value1>
[<prop2> <value2>]...)
Sets a property for the tests. If the test is not found, CMake will
report an error.
Test property values may be specified using generator expressions <#
manual:cmake-generator-expressions(7)> for tests created by the
add_test(NAME) <#command:add_test> signature.
Added in version 3.28: Visibility can be set in other directory scopes
using the following option:
DIRECTORY <dir>
The test properties will be set in the <dir> directory's scope.
CMake must already know about this directory, either by having
added it through a call to add_subdirectory() <#
command:add_subdirectory> or it being the top level source
directory. Relative paths are treated as relative to the current
source directory. <dir> may reference a binary directory.
See Also
o add_test() <#command:add_test>
o define_property() <#command:define_property>
o the more general set_property() <#command:set_property> command
o Properties on Tests <#test-properties> for the list of properties
known to CMake
source_group
Define a grouping for source files in IDE project generation. There
are two different signatures to create source groups.
source_group(<name> [FILES <src>...] [REGULAR_EXPRESSION <regex>])
source_group(TREE <root> [PREFIX <prefix>] [FILES <src>...])
Defines a group into which sources will be placed in project files.
This is intended to set up file tabs in Visual Studio. The group is
scoped in the directory where the command is called, and applies to
sources in targets created in that directory.
The options are:
TREE Added in version 3.8.
CMake will automatically detect, from <src> files paths, source
groups it needs to create, to keep structure of source groups
analogically to the actual files and directories structure in
the project. Paths of <src> files will be cut to be relative to
<root>. The command fails if the paths within src do not start
with root.
PREFIX Added in version 3.8.
Source group and files located directly in <root> path, will be
placed in <prefix> source groups.
FILES Any source file specified explicitly will be placed in group
<name>. Relative paths are interpreted with respect to the
current source directory.
REGULAR_EXPRESSION
Any source file whose name matches the regular expression will
be placed in group <name>.
If a source file matches multiple groups, the last group that
explicitly lists the file with FILES will be favored, if any. If no
group explicitly lists the file, the last group whose regular
expression matches the file will be favored.
The <name> of the group and <prefix> argument may contain forward
slashes or backslashes to specify subgroups. Backslashes need to be
escaped appropriately:
source_group(base/subdir ...)
source_group(outer\\inner ...)
source_group(TREE <root> PREFIX sources\\inc ...)
Added in version 3.18: Allow using forward slashes (/) to specify
subgroups.
For backwards compatibility, the short-hand signature
source_group(<name> <regex>)
is equivalent to
source_group(<name> REGULAR_EXPRESSION <regex>)
target_compile_definitions
Add compile definitions to a target.
target_compile_definitions(<target>
<INTERFACE|PUBLIC|PRIVATE> [items1...]
[<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])
Specifies compile definitions to use when compiling a given <target>.
The named <target> must have been created by a command such as
add_executable() <#command:add_executable> or add_library() <#
command:add_library> and must not be an ALIAS target <#alias-targets>.
The INTERFACE, PUBLIC and PRIVATE keywords are required to specify the
scope <#target-command-scope> of the following arguments. PRIVATE and
PUBLIC items will populate the COMPILE_DEFINITIONS <#
prop_tgt:COMPILE_DEFINITIONS> property of <target>. PUBLIC and
INTERFACE items will populate the INTERFACE_COMPILE_DEFINITIONS <#
prop_tgt:INTERFACE_COMPILE_DEFINITIONS> property of <target>. The
following arguments specify compile definitions. Repeated calls for
the same <target> append items in the order called.
Added in version 3.11: Allow setting INTERFACE items on IMPORTED
targets <#imported-targets>.
Arguments to target_compile_definitions may use generator expressions
with the syntax $<...>. See the cmake-generator-expressions(7) <#
manual:cmake-generator-expressions(7)> manual for available
expressions. See the cmake-buildsystem(7) <#manual:cmake-
buildsystem(7)> manual for more on defining buildsystem properties.
Any leading -D on an item will be removed. Empty items are ignored.
For example, the following are all equivalent:
target_compile_definitions(foo PUBLIC FOO)
target_compile_definitions(foo PUBLIC -DFOO) # -D removed
target_compile_definitions(foo PUBLIC "" FOO) # "" ignored
target_compile_definitions(foo PUBLIC -D FOO) # -D becomes "", then ignored
Definitions may optionally have values:
target_compile_definitions(foo PUBLIC FOO=1)
Note that many compilers treat -DFOO as equivalent to -DFOO=1, but
other tools may not recognize this in all circumstances (e.g.
IntelliSense).
See Also
o add_compile_definitions() <#command:add_compile_definitions>
o target_compile_features() <#command:target_compile_features>
o target_compile_options() <#command:target_compile_options>
o target_include_directories() <#command:target_include_directories>
o target_link_libraries() <#command:target_link_libraries>
o target_link_directories() <#command:target_link_directories>
o target_link_options() <#command:target_link_options>
o target_precompile_headers() <#command:target_precompile_headers>
o target_sources() <#command:target_sources>
target_compile_features
Added in version 3.1.
Add expected compiler features to a target.
target_compile_features(<target> <PRIVATE|PUBLIC|INTERFACE> <feature> [...])
Specifies compiler features required when compiling a given target. If
the feature is not listed in the CMAKE_C_COMPILE_FEATURES <#
variable:CMAKE_C_COMPILE_FEATURES>, CMAKE_CUDA_COMPILE_FEATURES <#
variable:CMAKE_CUDA_COMPILE_FEATURES>, or CMAKE_CXX_COMPILE_FEATURES <#
variable:CMAKE_CXX_COMPILE_FEATURES> variables, then an error will be
reported by CMake. If the use of the feature requires an additional
compiler flag, such as -std=gnu++11, the flag will be added
automatically.
The INTERFACE, PUBLIC and PRIVATE keywords are required to specify the
scope of the features. PRIVATE and PUBLIC items will populate the
COMPILE_FEATURES <#prop_tgt:COMPILE_FEATURES> property of <target>.
PUBLIC and INTERFACE items will populate the INTERFACE_COMPILE_FEATURES
<#prop_tgt:INTERFACE_COMPILE_FEATURES> property of <target>. Repeated
calls for the same <target> append items.
Added in version 3.11: Allow setting INTERFACE items on IMPORTED
targets <#imported-targets>.
The named <target> must have been created by a command such as
add_executable() <#command:add_executable> or add_library() <#
command:add_library> and must not be an ALIAS target <#alias-targets>.
for more on defining buildsystem properties.
Arguments to target_compile_features may use generator expressions with
the syntax $<...>. See the cmake-generator-expressions(7) <#
manual:cmake-generator-expressions(7)> manual for available
expressions. See the cmake-compile-features(7) <#manual:cmake-compile-
features(7)> manual for information on compile features and a list of
supported compilers.
See Also
o target_compile_definitions() <#command:target_compile_definitions>
o target_compile_options() <#command:target_compile_options>
o target_include_directories() <#command:target_include_directories>
o target_link_libraries() <#command:target_link_libraries>
o target_link_directories() <#command:target_link_directories>
o target_link_options() <#command:target_link_options>
o target_precompile_headers() <#command:target_precompile_headers>
o target_sources() <#command:target_sources>
target_compile_options
Add compile options to a target.
target_compile_options(<target> [BEFORE]
<INTERFACE|PUBLIC|PRIVATE> [items1...]
[<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])
Adds options to the COMPILE_OPTIONS <#prop_tgt:COMPILE_OPTIONS> or
INTERFACE_COMPILE_OPTIONS <#prop_tgt:INTERFACE_COMPILE_OPTIONS> target
properties. These options are used when compiling the given <target>,
which must have been created by a command such as add_executable() <#
command:add_executable> or add_library() <#command:add_library> and
must not be an ALIAS target <#alias-targets>.
Note:
These options are not used when linking the target. See the
target_link_options() <#command:target_link_options> command for
that.
Arguments
If BEFORE is specified, the content will be prepended to the property
instead of being appended. See policy CMP0101 <#policy:CMP0101> which
affects whether BEFORE will be ignored in certain cases.
The INTERFACE, PUBLIC and PRIVATE keywords are required to specify the
scope <#target-command-scope> of the following arguments. PRIVATE and
PUBLIC items will populate the COMPILE_OPTIONS <#
prop_tgt:COMPILE_OPTIONS> property of <target>. PUBLIC and INTERFACE
items will populate the INTERFACE_COMPILE_OPTIONS <#
prop_tgt:INTERFACE_COMPILE_OPTIONS> property of <target>. The
following arguments specify compile options. Repeated calls for the
same <target> append items in the order called.
Added in version 3.11: Allow setting INTERFACE items on IMPORTED
targets <#imported-targets>.
Arguments to target_compile_options may use generator expressions with
the syntax $<...>. See the cmake-generator-expressions(7) <#
manual:cmake-generator-expressions(7)> manual for available
expressions. See the cmake-buildsystem(7) <#manual:cmake-
buildsystem(7)> manual for more on defining buildsystem properties.
Option De-duplication
The final set of options used for a target is constructed by
accumulating options from the current target and the usage requirements
of its dependencies. The set of options is de-duplicated to avoid
repetition.
Added in version 3.12: While beneficial for individual options, the
de-duplication step can break up option groups. For example, -option A
-option B becomes -option A B. One may specify a group of options
using shell-like quoting along with a SHELL: prefix. The SHELL: prefix
is dropped, and the rest of the option string is parsed using the
separate_arguments() <#command:separate_arguments> UNIX_COMMAND mode.
For example, "SHELL:-option A" "SHELL:-option B" becomes -option A
-option B.
See Also
o This command can be used to add any options. However, for adding
preprocessor definitions and include directories it is recommended to
use the more specific commands target_compile_definitions() <#
command:target_compile_definitions> and target_include_directories()
<#command:target_include_directories>.
o For directory-wide settings, there is the command
add_compile_options() <#command:add_compile_options>.
o For file-specific settings, there is the source file property
COMPILE_OPTIONS <#prop_sf:COMPILE_OPTIONS>.
o This command adds compile options for all languages in a target. Use
the COMPILE_LANGUAGE <#genex:COMPILE_LANGUAGE> generator expression
to specify per-language compile options.
o target_compile_features() <#command:target_compile_features>
o target_link_libraries() <#command:target_link_libraries>
o target_link_directories() <#command:target_link_directories>
o target_link_options() <#command:target_link_options>
o target_precompile_headers() <#command:target_precompile_headers>
o target_sources() <#command:target_sources>
o CMAKE_<LANG>_FLAGS <#variable:CMAKE_<LANG>_FLAGS> and
CMAKE_<LANG>_FLAGS_<CONFIG> <#variable:CMAKE_<LANG>_FLAGS_<CONFIG>>
add language-wide flags passed to all invocations of the compiler.
This includes invocations that drive compiling and those that drive
linking.
target_include_directories
Add include directories to a target.
target_include_directories(<target> [SYSTEM] [AFTER|BEFORE]
<INTERFACE|PUBLIC|PRIVATE> [items1...]
[<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])
Specifies include directories to use when compiling a given target.
The named <target> must have been created by a command such as
add_executable() <#command:add_executable> or add_library() <#
command:add_library> and must not be an ALIAS target <#alias-targets>.
By using AFTER or BEFORE explicitly, you can select between appending
and prepending, independent of the default.
The INTERFACE, PUBLIC and PRIVATE keywords are required to specify the
scope <#target-command-scope> of the following arguments. PRIVATE and
PUBLIC items will populate the INCLUDE_DIRECTORIES <#
prop_tgt:INCLUDE_DIRECTORIES> property of <target>. PUBLIC and
INTERFACE items will populate the INTERFACE_INCLUDE_DIRECTORIES <#
prop_tgt:INTERFACE_INCLUDE_DIRECTORIES> property of <target>. The
following arguments specify include directories.
Added in version 3.11: Allow setting INTERFACE items on IMPORTED
targets <#imported-targets>.
Repeated calls for the same <target> append items in the order called.
If SYSTEM is specified, the compiler will be told the directories are
meant as system include directories on some platforms. This may have
effects such as suppressing warnings or skipping the contained headers
in dependency calculations (see compiler documentation). Additionally,
system include directories are searched after normal include
directories regardless of the order specified.
If SYSTEM is used together with PUBLIC or INTERFACE, the
INTERFACE_SYSTEM_INCLUDE_DIRECTORIES <#
prop_tgt:INTERFACE_SYSTEM_INCLUDE_DIRECTORIES> target property will be
populated with the specified directories.
Arguments to target_include_directories may use generator expressions
with the syntax $<...>. See the cmake-generator-expressions(7) <#
manual:cmake-generator-expressions(7)> manual for available
expressions. See the cmake-buildsystem(7) <#manual:cmake-
buildsystem(7)> manual for more on defining buildsystem properties.
Specified include directories may be absolute paths or relative paths.
A relative path will be interpreted as relative to the current source
directory (i.e. CMAKE_CURRENT_SOURCE_DIR <#
variable:CMAKE_CURRENT_SOURCE_DIR>) and converted to an absolute path
before storing it in the associated target property. If the path
starts with a generator expression, it will always be assumed to be an
absolute path (with one exception noted below) and will be used
unmodified.
Include directories usage requirements commonly differ between the
build-tree and the install-tree. The BUILD_INTERFACE <#
genex:BUILD_INTERFACE> and INSTALL_INTERFACE <#genex:INSTALL_INTERFACE>
generator expressions can be used to describe separate usage
requirements based on the usage location. Relative paths are allowed
within the INSTALL_INTERFACE <#genex:INSTALL_INTERFACE> expression and
are interpreted as relative to the installation prefix. Relative paths
should not be used in BUILD_INTERFACE <#genex:BUILD_INTERFACE>
expressions because they will not be converted to absolute. For
example:
target_include_directories(mylib PUBLIC
$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include/mylib>
$<INSTALL_INTERFACE:include/mylib> # <prefix>/include/mylib
)
Creating Relocatable Packages
Note that it is not advisable to populate the INSTALL_INTERFACE <#
genex:INSTALL_INTERFACE> of the INTERFACE_INCLUDE_DIRECTORIES <#
prop_tgt:INTERFACE_INCLUDE_DIRECTORIES> of a target with absolute paths
to the include directories of dependencies. That would hard-code into
installed packages the include directory paths for dependencies as
found on the machine the package was made on.
The INSTALL_INTERFACE <#genex:INSTALL_INTERFACE> of the
INTERFACE_INCLUDE_DIRECTORIES <#prop_tgt:INTERFACE_INCLUDE_DIRECTORIES>
is only suitable for specifying the required include directories for
headers provided with the target itself, not those provided by the
transitive dependencies listed in its INTERFACE_LINK_LIBRARIES <#
prop_tgt:INTERFACE_LINK_LIBRARIES> target property. Those dependencies
should themselves be targets that specify their own header locations in
INTERFACE_INCLUDE_DIRECTORIES <#
prop_tgt:INTERFACE_INCLUDE_DIRECTORIES>.
See the Creating Relocatable Packages <#creating-relocatable-packages>
section of the cmake-packages(7) <#manual:cmake-packages(7)> manual for
discussion of additional care that must be taken when specifying usage
requirements while creating packages for redistribution.
See Also
o include_directories() <#command:include_directories>
o target_compile_definitions() <#command:target_compile_definitions>
o target_compile_features() <#command:target_compile_features>
o target_compile_options() <#command:target_compile_options>
o target_link_libraries() <#command:target_link_libraries>
o target_link_directories() <#command:target_link_directories>
o target_link_options() <#command:target_link_options>
o target_precompile_headers() <#command:target_precompile_headers>
o target_sources() <#command:target_sources>
target_link_directories
Added in version 3.13.
Add link directories to a target.
target_link_directories(<target> [BEFORE]
<INTERFACE|PUBLIC|PRIVATE> [items1...]
[<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])
Specifies the paths in which the linker should search for libraries
when linking a given target. Each item can be an absolute or relative
path, with the latter being interpreted as relative to the current
source directory. These items will be added to the link command.
The named <target> must have been created by a command such as
add_executable() <#command:add_executable> or add_library() <#
command:add_library> and must not be an ALIAS target <#alias-targets>.
The INTERFACE, PUBLIC and PRIVATE keywords are required to specify the
scope <#target-command-scope> of the items that follow them. PRIVATE
and PUBLIC items will populate the LINK_DIRECTORIES <#
prop_tgt:LINK_DIRECTORIES> property of <target>. PUBLIC and INTERFACE
items will populate the INTERFACE_LINK_DIRECTORIES <#
prop_tgt:INTERFACE_LINK_DIRECTORIES> property of <target> (IMPORTED
targets <#imported-targets> only support INTERFACE items). Each item
specifies a link directory and will be converted to an absolute path if
necessary before adding it to the relevant property. Repeated calls
for the same <target> append items in the order called.
If BEFORE is specified, the content will be prepended to the relevant
property instead of being appended.
Arguments to target_link_directories may use generator expressions with
the syntax $<...>. See the cmake-generator-expressions(7) <#
manual:cmake-generator-expressions(7)> manual for available
expressions. See the cmake-buildsystem(7) <#manual:cmake-
buildsystem(7)> manual for more on defining buildsystem properties.
Note:
This command is rarely necessary and should be avoided where there
are other choices. Prefer to pass full absolute paths to libraries
where possible, since this ensures the correct library will always
be linked. The find_library() <#command:find_library> command
provides the full path, which can generally be used directly in
calls to target_link_libraries() <#command:target_link_libraries>.
Situations where a library search path may be needed include:
o Project generators like Xcode where the user can switch target
architecture at build time, but a full path to a library cannot be
used because it only provides one architecture (i.e. it is not a
universal binary).
o Libraries may themselves have other private library dependencies
that expect to be found via RPATH mechanisms, but some linkers are
not able to fully decode those paths (e.g. due to the presence of
things like $ORIGIN).
See Also
o link_directories() <#command:link_directories>
o target_compile_definitions() <#command:target_compile_definitions>
o target_compile_features() <#command:target_compile_features>
o target_compile_options() <#command:target_compile_options>
o target_include_directories() <#command:target_include_directories>
o target_link_libraries() <#command:target_link_libraries>
o target_link_options() <#command:target_link_options>
o target_precompile_headers() <#command:target_precompile_headers>
o target_sources() <#command:target_sources>
target_link_libraries
Specify libraries or flags to use when linking a given target and/or
its dependents. Usage requirements <#target-usage-requirements> from
linked library targets will be propagated. Usage requirements of a
target's dependencies affect compilation of its own sources.
Overview
This command has several signatures as detailed in subsections below.
All of them have the general form
target_link_libraries(<target> ... <item>... ...)
The named <target> must have been created by a command such as
add_executable() <#command:add_executable> or add_library() <#
command:add_library> and must not be an ALIAS target <#alias-targets>.
If policy CMP0079 <#policy:CMP0079> is not set to NEW then the target
must have been created in the current directory. Repeated calls for
the same <target> append items in the order called.
Added in version 3.13: The <target> doesn't have to be defined in the
same directory as the target_link_libraries call.
Each <item> may be:
o A library target name: The generated link line will have the full
path to the linkable library file associated with the target. The
buildsystem will have a dependency to re-link <target> if the library
file changes.
The named target must be created by add_library() <#
command:add_library> within the project or as an IMPORTED library <#
imported-targets>. If it is created within the project an ordering
dependency will automatically be added in the build system to make
sure the named library target is up-to-date before the <target>
links.
If an imported library has the IMPORTED_NO_SONAME <#
prop_tgt:IMPORTED_NO_SONAME> target property set, CMake may ask the
linker to search for the library instead of using the full path (e.g.
/usr/lib/libfoo.so becomes -lfoo).
The full path to the target's artifact will be quoted/escaped for the
shell automatically.
o A full path to a library file: The generated link line will normally
preserve the full path to the file. The buildsystem will have a
dependency to re-link <target> if the library file changes.
There are some cases where CMake may ask the linker to search for the
library (e.g. /usr/lib/libfoo.so becomes -lfoo), such as when a
shared library is detected to have no SONAME field. See policy
CMP0060 <#policy:CMP0060> for discussion of another case.
If the library file is in a macOS framework, the Headers directory of
the framework will also be processed as a usage requirement <#target-
usage-requirements>. This has the same effect as passing the
framework directory as an include directory.
Added in version 3.28: The library file may point to a .xcframework
folder on Apple platforms. If it does, the target will get the
selected library's Headers directory as a usage requirement.
Added in version 3.8: On Visual Studio Generators <#visual-studio-
generators> for VS 2010 and above, library files ending in .targets
will be treated as MSBuild targets files and imported into generated
project files. This is not supported by other generators.
The full path to the library file will be quoted/escaped for the
shell automatically.
o A plain library name: The generated link line will ask the linker to
search for the library (e.g. foo becomes -lfoo or foo.lib).
The library name/flag is treated as a command-line string fragment
and will be used with no extra quoting or escaping.
o A link flag: Item names starting with -, but not -l or -framework,
are treated as linker flags. Note that such flags will be treated
like any other library link item for purposes of transitive
dependencies, so they are generally safe to specify only as private
link items that will not propagate to dependents.
Link flags specified here are inserted into the link command in the
same place as the link libraries. This might not be correct,
depending on the linker. Use the LINK_OPTIONS <#
prop_tgt:LINK_OPTIONS> target property or target_link_options() <#
command:target_link_options> command to add link flags explicitly.
The flags will then be placed at the toolchain-defined flag position
in the link command.
Added in version 3.13: LINK_OPTIONS <#prop_tgt:LINK_OPTIONS> target
property and target_link_options() <#command:target_link_options>
command. For earlier versions of CMake, use LINK_FLAGS <#
prop_tgt:LINK_FLAGS> property instead.
The link flag is treated as a command-line string fragment and will
be used with no extra quoting or escaping.
o A generator expression: A $<...> generator expression <#manual:cmake-
generator-expressions(7)> may evaluate to any of the above items or
to a semicolon-separated list <#cmake-language-lists> of them. If
the ... contains any ; characters, e.g. after evaluation of a ${list}
variable, be sure to use an explicitly quoted argument "$<...>" so
that this command receives it as a single <item>.
Additionally, a generator expression may be used as a fragment of any
of the above items, e.g. foo$<1:_d>.
Note that generator expressions will not be used in OLD handling of
policy CMP0003 <#policy:CMP0003> or policy CMP0004 <#policy:CMP0004>.
o A debug, optimized, or general keyword immediately followed by
another <item>. The item following such a keyword will be used only
for the corresponding build configuration. The debug keyword
corresponds to the Debug configuration (or to configurations named in
the DEBUG_CONFIGURATIONS <#prop_gbl:DEBUG_CONFIGURATIONS> global
property if it is set). The optimized keyword corresponds to all
other configurations. The general keyword corresponds to all
configurations, and is purely optional. Higher granularity may be
achieved for per-configuration rules by creating and linking to
IMPORTED library targets <#imported-targets>. These keywords are
interpreted immediately by this command and therefore have no special
meaning when produced by a generator expression.
Items containing ::, such as Foo::Bar, are assumed to be IMPORTED <#
imported-targets> or ALIAS <#alias-targets> library target names and
will cause an error if no such target exists. See policy CMP0028 <#
policy:CMP0028>.
See the CMAKE_LINK_LIBRARIES_STRATEGY <#
variable:CMAKE_LINK_LIBRARIES_STRATEGY> variable and corresponding
LINK_LIBRARIES_STRATEGY <#prop_tgt:LINK_LIBRARIES_STRATEGY> target
property for details on how CMake orders direct link dependencies on
linker command lines.
See the cmake-buildsystem(7) <#manual:cmake-buildsystem(7)> manual for
more on defining buildsystem properties.
Libraries for a Target and/or its Dependents
target_link_libraries(<target>
<PRIVATE|PUBLIC|INTERFACE> <item>...
[<PRIVATE|PUBLIC|INTERFACE> <item>...]...)
The PUBLIC, PRIVATE and INTERFACE scope <#target-command-scope>
keywords can be used to specify both the link dependencies and the link
interface in one command.
Libraries and targets following PUBLIC are linked to, and are made part
of the link interface. Libraries and targets following PRIVATE are
linked to, but are not made part of the link interface. Libraries
following INTERFACE are appended to the link interface and are not used
for linking <target>.
Libraries for both a Target and its Dependents
target_link_libraries(<target> <item>...)
Library dependencies are transitive by default with this signature.
When this target is linked into another target then the libraries
linked to this target will appear on the link line for the other target
too. This transitive "link interface" is stored in the
INTERFACE_LINK_LIBRARIES <#prop_tgt:INTERFACE_LINK_LIBRARIES> target
property and may be overridden by setting the property directly. When
CMP0022 <#policy:CMP0022> is not set to NEW, transitive linking is
built in but may be overridden by the LINK_INTERFACE_LIBRARIES <#
prop_tgt:LINK_INTERFACE_LIBRARIES> property. Calls to other signatures
of this command may set the property making any libraries linked
exclusively by this signature private.
Libraries for a Target and/or its Dependents (Legacy)
target_link_libraries(<target>
<LINK_PRIVATE|LINK_PUBLIC> <lib>...
[<LINK_PRIVATE|LINK_PUBLIC> <lib>...]...)
The LINK_PUBLIC and LINK_PRIVATE modes can be used to specify both the
link dependencies and the link interface in one command.
This signature is for compatibility only. Prefer the PUBLIC or PRIVATE
keywords instead.
Libraries and targets following LINK_PUBLIC are linked to, and are made
part of the INTERFACE_LINK_LIBRARIES <#
prop_tgt:INTERFACE_LINK_LIBRARIES>. If policy CMP0022 <#
policy:CMP0022> is not NEW, they are also made part of the
LINK_INTERFACE_LIBRARIES <#prop_tgt:LINK_INTERFACE_LIBRARIES>.
Libraries and targets following LINK_PRIVATE are linked to, but are not
made part of the INTERFACE_LINK_LIBRARIES <#
prop_tgt:INTERFACE_LINK_LIBRARIES> (or LINK_INTERFACE_LIBRARIES <#
prop_tgt:LINK_INTERFACE_LIBRARIES>).
Libraries for Dependents Only (Legacy)
target_link_libraries(<target> LINK_INTERFACE_LIBRARIES <item>...)
The LINK_INTERFACE_LIBRARIES mode appends the libraries to the
INTERFACE_LINK_LIBRARIES <#prop_tgt:INTERFACE_LINK_LIBRARIES> target
property instead of using them for linking. If policy CMP0022 <#
policy:CMP0022> is not NEW, then this mode also appends libraries to
the LINK_INTERFACE_LIBRARIES <#prop_tgt:LINK_INTERFACE_LIBRARIES> and
its per-configuration equivalent.
This signature is for compatibility only. Prefer the INTERFACE mode
instead.
Libraries specified as debug are wrapped in a generator expression to
correspond to debug builds. If policy CMP0022 <#policy:CMP0022> is not
NEW, the libraries are also appended to the
LINK_INTERFACE_LIBRARIES_DEBUG <#
prop_tgt:LINK_INTERFACE_LIBRARIES_<CONFIG>> property (or to the
properties corresponding to configurations listed in the
DEBUG_CONFIGURATIONS <#prop_gbl:DEBUG_CONFIGURATIONS> global property
if it is set). Libraries specified as optimized are appended to the
INTERFACE_LINK_LIBRARIES <#prop_tgt:INTERFACE_LINK_LIBRARIES> property.
If policy CMP0022 <#policy:CMP0022> is not NEW, they are also appended
to the LINK_INTERFACE_LIBRARIES <#prop_tgt:LINK_INTERFACE_LIBRARIES>
property. Libraries specified as general (or without any keyword) are
treated as if specified for both debug and optimized.
Linking Object Libraries
Added in version 3.12.
Object Libraries <#object-libraries> may be used as the <target>
(first) argument of target_link_libraries to specify dependencies of
their sources on other libraries. For example, the code
add_library(A SHARED a.c)
target_compile_definitions(A PUBLIC A)
add_library(obj OBJECT obj.c)
target_compile_definitions(obj PUBLIC OBJ)
target_link_libraries(obj PUBLIC A)
compiles obj.c with -DA -DOBJ and establishes usage requirements for
obj that propagate to its dependents.
Normal libraries and executables may link to Object Libraries <#object-
libraries> to get their objects and usage requirements. Continuing the
above example, the code
add_library(B SHARED b.c)
target_link_libraries(B PUBLIC obj)
compiles b.c with -DA -DOBJ, creates shared library B with object files
from b.c and obj.c, and links B to A. Furthermore, the code
add_executable(main main.c)
target_link_libraries(main B)
compiles main.c with -DA -DOBJ and links executable main to B and A.
The object library's usage requirements are propagated transitively
through B, but its object files are not.
Object Libraries <#object-libraries> may "link" to other object
libraries to get usage requirements, but since they do not have a link
step nothing is done with their object files. Continuing from the
above example, the code:
add_library(obj2 OBJECT obj2.c)
target_link_libraries(obj2 PUBLIC obj)
add_executable(main2 main2.c)
target_link_libraries(main2 obj2)
compiles obj2.c with -DA -DOBJ, creates executable main2 with object
files from main2.c and obj2.c, and links main2 to A.
In other words, when Object Libraries <#object-libraries> appear in a
target's INTERFACE_LINK_LIBRARIES <#prop_tgt:INTERFACE_LINK_LIBRARIES>
property they will be treated as Interface Libraries <#interface-
libraries>, but when they appear in a target's LINK_LIBRARIES <#
prop_tgt:LINK_LIBRARIES> property their object files will be included
in the link too.
Linking Object Libraries via $<TARGET_OBJECTS>
Added in version 3.21.
The object files associated with an object library may be referenced by
the $<TARGET_OBJECTS> <#genex:TARGET_OBJECTS> generator expression.
Such object files are placed on the link line before all libraries,
regardless of their relative order. Additionally, an ordering
dependency will be added to the build system to make sure the object
library is up-to-date before the dependent target links. For example,
the code
add_library(obj3 OBJECT obj3.c)
target_compile_definitions(obj3 PUBLIC OBJ3)
add_executable(main3 main3.c)
target_link_libraries(main3 PRIVATE a3 $<TARGET_OBJECTS:obj3> b3)
links executable main3 with object files from main3.c and obj3.c
followed by the a3 and b3 libraries. main3.c is not compiled with
usage requirements from obj3, such as -DOBJ3.
This approach can be used to achieve transitive inclusion of object
files in link lines as usage requirements. Continuing the above
example, the code
add_library(iface_obj3 INTERFACE)
target_link_libraries(iface_obj3 INTERFACE obj3 $<TARGET_OBJECTS:obj3>)
creates an interface library iface_obj3 that forwards the obj3 usage
requirements and adds the obj3 object files to dependents' link lines.
The code
add_executable(use_obj3 use_obj3.c)
target_link_libraries(use_obj3 PRIVATE iface_obj3)
compiles use_obj3.c with -DOBJ3 and links executable use_obj3 with
object files from use_obj3.c and obj3.c.
This also works transitively through a static library. Since a static
library does not link, it does not consume the object files from object
libraries referenced this way. Instead, the object files become
transitive link dependencies of the static library. Continuing the
above example, the code
add_library(static3 STATIC static3.c)
target_link_libraries(static3 PRIVATE iface_obj3)
add_executable(use_static3 use_static3.c)
target_link_libraries(use_static3 PRIVATE static3)
compiles static3.c with -DOBJ3 and creates libstatic3.a using only its
own object file. use_static3.c is compiled without -DOBJ3 because the
usage requirement is not transitive through the private dependency of
static3. However, the link dependencies of static3 are propagated,
including the iface_obj3 reference to $<TARGET_OBJECTS:obj3>. The
use_static3 executable is created with object files from use_static3.c
and obj3.c, and linked to library libstatic3.a.
When using this approach, it is the project's responsibility to avoid
linking multiple dependent binaries to iface_obj3, because they will
all get the obj3 object files on their link lines.
Note:
Referencing $<TARGET_OBJECTS> <#genex:TARGET_OBJECTS> in
target_link_libraries calls worked in versions of CMake prior to
3.21 for some cases, but was not fully supported:
o It did not place the object files before libraries on link lines.
o It did not add an ordering dependency on the object library.
o It did not work in Xcode with multiple architectures.
Cyclic Dependencies of Static Libraries
The library dependency graph is normally acyclic (a DAG), but in the
case of mutually-dependent STATIC libraries CMake allows the graph to
contain cycles (strongly connected components). When another target
links to one of the libraries, CMake repeats the entire connected
component. For example, the code
add_library(A STATIC a.c)
add_library(B STATIC b.c)
target_link_libraries(A B)
target_link_libraries(B A)
add_executable(main main.c)
target_link_libraries(main A)
links main to A B A B. While one repetition is usually sufficient,
pathological object file and symbol arrangements can require more. One
may handle such cases by using the LINK_INTERFACE_MULTIPLICITY <#
prop_tgt:LINK_INTERFACE_MULTIPLICITY> target property or by manually
repeating the component in the last target_link_libraries call.
However, if two archives are really so interdependent they should
probably be combined into a single archive, perhaps by using Object
Libraries <#object-libraries>.
Creating Relocatable Packages
Note that it is not advisable to populate the INTERFACE_LINK_LIBRARIES
<#prop_tgt:INTERFACE_LINK_LIBRARIES> of a target with absolute paths to
dependencies. That would hard-code into installed packages the library
file paths for dependencies as found on the machine the package was
made on.
See the Creating Relocatable Packages <#creating-relocatable-packages>
section of the cmake-packages(7) <#manual:cmake-packages(7)> manual for
discussion of additional care that must be taken when specifying usage
requirements while creating packages for redistribution.
See Also
o target_compile_definitions() <#command:target_compile_definitions>
o target_compile_features() <#command:target_compile_features>
o target_compile_options() <#command:target_compile_options>
o target_include_directories() <#command:target_include_directories>
o target_link_directories() <#command:target_link_directories>
o target_link_options() <#command:target_link_options>
o target_precompile_headers() <#command:target_precompile_headers>
o target_sources() <#command:target_sources>
target_link_options
Added in version 3.13.
Add options to the link step for an executable, shared library or
module library target.
target_link_options(<target> [BEFORE]
<INTERFACE|PUBLIC|PRIVATE> [items1...]
[<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])
The named <target> must have been created by a command such as
add_executable() <#command:add_executable> or add_library() <#
command:add_library> and must not be an ALIAS target <#alias-targets>.
This command can be used to add any link options, but alternative
commands exist to add libraries (target_link_libraries() <#
command:target_link_libraries> or link_libraries() <#
command:link_libraries>). See documentation of the directory <#
prop_dir:LINK_OPTIONS> and target <#prop_tgt:LINK_OPTIONS> LINK_OPTIONS
properties.
Note:
This command cannot be used to add options for static library
targets, since they do not use a linker. To add archiver or MSVC
librarian flags, see the STATIC_LIBRARY_OPTIONS <#
prop_tgt:STATIC_LIBRARY_OPTIONS> target property.
If BEFORE is specified, the content will be prepended to the property
instead of being appended.
The INTERFACE, PUBLIC and PRIVATE keywords are required to specify the
scope <#target-command-scope> of the following arguments. PRIVATE and
PUBLIC items will populate the LINK_OPTIONS <#prop_tgt:LINK_OPTIONS>
property of <target>. PUBLIC and INTERFACE items will populate the
INTERFACE_LINK_OPTIONS <#prop_tgt:INTERFACE_LINK_OPTIONS> property of
<target>. The following arguments specify link options. Repeated
calls for the same <target> append items in the order called.
Note:
IMPORTED targets <#imported-targets> only support INTERFACE items.
Arguments to target_link_options may use generator expressions with the
syntax $<...>. See the cmake-generator-expressions(7) <#manual:cmake-
generator-expressions(7)> manual for available expressions. See the
cmake-buildsystem(7) <#manual:cmake-buildsystem(7)> manual for more on
defining buildsystem properties.
Host And Device Specific Link Options
Added in version 3.18: When a device link step is involved, which is
controlled by CUDA_SEPARABLE_COMPILATION <#
prop_tgt:CUDA_SEPARABLE_COMPILATION> and CUDA_RESOLVE_DEVICE_SYMBOLS <#
prop_tgt:CUDA_RESOLVE_DEVICE_SYMBOLS> properties and policy CMP0105 <#
policy:CMP0105>, the raw options will be delivered to the host and
device link steps (wrapped in -Xcompiler or equivalent for device
link). Options wrapped with $<DEVICE_LINK:...> <#genex:DEVICE_LINK>
generator expression will be used only for the device link step.
Options wrapped with $<HOST_LINK:...> <#genex:HOST_LINK> generator
expression will be used only for the host link step.
Option De-duplication
The final set of options used for a target is constructed by
accumulating options from the current target and the usage requirements
of its dependencies. The set of options is de-duplicated to avoid
repetition.
Added in version 3.12: While beneficial for individual options, the
de-duplication step can break up option groups. For example, -option A
-option B becomes -option A B. One may specify a group of options
using shell-like quoting along with a SHELL: prefix. The SHELL: prefix
is dropped, and the rest of the option string is parsed using the
separate_arguments() <#command:separate_arguments> UNIX_COMMAND mode.
For example, "SHELL:-option A" "SHELL:-option B" becomes -option A
-option B.
Handling Compiler Driver Differences
To pass options to the linker tool, each compiler driver has its own
syntax. The LINKER: prefix and , separator can be used to specify, in
a portable way, options to pass to the linker tool. LINKER: is replaced
by the appropriate driver option and , by the appropriate driver
separator. The driver prefix and driver separator are given by the
values of the CMAKE_<LANG>_LINKER_WRAPPER_FLAG <#
variable:CMAKE_<LANG>_LINKER_WRAPPER_FLAG> and
CMAKE_<LANG>_LINKER_WRAPPER_FLAG_SEP <#
variable:CMAKE_<LANG>_LINKER_WRAPPER_FLAG_SEP> variables.
For example, "LINKER:-z,defs" becomes -Xlinker -z -Xlinker defs for
Clang and -Wl,-z,defs for GNU GCC.
The LINKER: prefix can be specified as part of a SHELL: prefix
expression.
The LINKER: prefix supports, as an alternative syntax, specification of
arguments using the SHELL: prefix and space as separator. The previous
example then becomes "LINKER:SHELL:-z defs".
Note:
Specifying the SHELL: prefix anywhere other than at the beginning of
the LINKER: prefix is not supported.
See Also
o target_compile_definitions() <#command:target_compile_definitions>
o target_compile_features() <#command:target_compile_features>
o target_compile_options() <#command:target_compile_options>
o target_include_directories() <#command:target_include_directories>
o target_link_libraries() <#command:target_link_libraries>
o target_link_directories() <#command:target_link_directories>
o target_precompile_headers() <#command:target_precompile_headers>
o target_sources() <#command:target_sources>
o CMAKE_<LANG>_FLAGS <#variable:CMAKE_<LANG>_FLAGS> and
CMAKE_<LANG>_FLAGS_<CONFIG> <#variable:CMAKE_<LANG>_FLAGS_<CONFIG>>
add language-wide flags passed to all invocations of the compiler.
This includes invocations that drive compiling and those that drive
linking.
target_precompile_headers
Added in version 3.16.
Add a list of header files to precompile.
Precompiling header files can speed up compilation by creating a
partially processed version of some header files, and then using that
version during compilations rather than repeatedly parsing the original
headers.
Main Form
target_precompile_headers(<target>
<INTERFACE|PUBLIC|PRIVATE> [header1...]
[<INTERFACE|PUBLIC|PRIVATE> [header2...] ...])
The command adds header files to the PRECOMPILE_HEADERS <#
prop_tgt:PRECOMPILE_HEADERS> and/or INTERFACE_PRECOMPILE_HEADERS <#
prop_tgt:INTERFACE_PRECOMPILE_HEADERS> target properties of <target>.
The named <target> must have been created by a command such as
add_executable() <#command:add_executable> or add_library() <#
command:add_library> and must not be an ALIAS target <#alias-targets>.
The INTERFACE, PUBLIC and PRIVATE keywords are required to specify the
scope <#target-command-scope> of the following arguments. PRIVATE and
PUBLIC items will populate the PRECOMPILE_HEADERS <#
prop_tgt:PRECOMPILE_HEADERS> property of <target>. PUBLIC and
INTERFACE items will populate the INTERFACE_PRECOMPILE_HEADERS <#
prop_tgt:INTERFACE_PRECOMPILE_HEADERS> property of <target> (IMPORTED
targets <#imported-targets> only support INTERFACE items). Repeated
calls for the same <target> will append items in the order called.
Projects should generally avoid using PUBLIC or INTERFACE for targets
that will be exported <#export>, or they should at least use the
$<BUILD_INTERFACE:...> <#genex:BUILD_INTERFACE> generator expression to
prevent precompile headers from appearing in an installed exported
target. Consumers of a target should typically be in control of what
precompile headers they use, not have precompile headers forced on them
by the targets being consumed (since precompile headers are not
typically usage requirements). A notable exception to this is where an
interface library <#interface-libraries> is created to define a
commonly used set of precompile headers in one place and then other
targets link to that interface library privately. In this case, the
interface library exists specifically to propagate the precompile
headers to its consumers and the consumer is effectively still in
control, since it decides whether to link to the interface library or
not.
The list of header files is used to generate a header file named
cmake_pch.h|xx which is used to generate the precompiled header file
(.pch, .gch, .pchi) artifact. The cmake_pch.h|xx header file will be
force included (-include for GCC, /FI for MSVC) to all source files, so
sources do not need to have #include "pch.h".
Header file names specified with angle brackets (e.g. <unordered_map>)
or explicit double quotes (escaped for the cmake-language(7) <#
manual:cmake-language(7)>, e.g. [["other_header.h"]]) will be treated
as is, and include directories must be available for the compiler to
find them. Other header file names (e.g. project_header.h) are
interpreted as being relative to the current source directory (e.g.
CMAKE_CURRENT_SOURCE_DIR <#variable:CMAKE_CURRENT_SOURCE_DIR>) and will
be included by absolute path. For example:
target_precompile_headers(myTarget
PUBLIC
project_header.h
PRIVATE
[["other_header.h"]]
<unordered_map>
)
for more on defining buildsystem properties.
Arguments to target_precompile_headers may use generator expressions
with the syntax $<...>. See the cmake-generator-expressions(7) <#
manual:cmake-generator-expressions(7)> manual for available
expressions. The $<COMPILE_LANGUAGE:...> <#genex:COMPILE_LANGUAGE>
generator expression is particularly useful for specifying a
language-specific header to precompile for only one language (e.g. CXX
and not C). In this case, header file names that are not explicitly in
double quotes or angle brackets must be specified by absolute path.
Also, when specifying angle brackets inside a generator expression, be
sure to encode the closing > as $<ANGLE-R> <#genex:ANGLE-R>. For
example:
target_precompile_headers(mylib PRIVATE
"$<$Reusing Precompile Headers
The command also supports a second signature which can be used to
specify that one target reuses a precompiled header file artifact from
another target instead of generating its own:
target_precompile_headers(<target> REUSE_FROM <other_target>)
This form sets the PRECOMPILE_HEADERS_REUSE_FROM <#
prop_tgt:PRECOMPILE_HEADERS_REUSE_FROM> property to <other_target> and
adds a dependency such that <target> will depend on <other_target>.
CMake will halt with an error if the PRECOMPILE_HEADERS <#
prop_tgt:PRECOMPILE_HEADERS> property of <target> is already set when
the REUSE_FROM form is used.
Note:
The REUSE_FROM form requires the same set of compiler options,
compiler flags and compiler definitions for both <target> and
<other_target>. Some compilers (e.g. GCC) may issue a warning if
the precompiled header file cannot be used (-Winvalid-pch).
See Also
o To disable precompile headers for specific targets, see the
DISABLE_PRECOMPILE_HEADERS <#prop_tgt:DISABLE_PRECOMPILE_HEADERS>
target property.
o To prevent precompile headers from being used when compiling a
specific source file, see the SKIP_PRECOMPILE_HEADERS <#
prop_sf:SKIP_PRECOMPILE_HEADERS> source file property.
o target_compile_definitions() <#command:target_compile_definitions>
o target_compile_features() <#command:target_compile_features>
o target_compile_options() <#command:target_compile_options>
o target_include_directories() <#command:target_include_directories>
o target_link_libraries() <#command:target_link_libraries>
o target_link_directories() <#command:target_link_directories>
o target_link_options() <#command:target_link_options>
o target_sources() <#command:target_sources>
target_sources
Added in version 3.1.
Add sources to a target.
target_sources(<target>
<INTERFACE|PUBLIC|PRIVATE> [items1...]
[<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])
Specifies sources to use when building a target and/or its dependents.
The named <target> must have been created by a command such as
add_executable() <#command:add_executable> or add_library() <#
command:add_library> or add_custom_target() <#
command:add_custom_target> and must not be an ALIAS target <#alias-
targets>. The <items> may use generator expressions <#manual:cmake-
generator-expressions(7)>.
Added in version 3.20: <target> can be a custom target.
The INTERFACE, PUBLIC and PRIVATE keywords are required to specify the
scope <#target-command-scope> of the source file paths (<items>) that
follow them. PRIVATE and PUBLIC items will populate the SOURCES <#
prop_tgt:SOURCES> property of <target>, which are used when building
the target itself. PUBLIC and INTERFACE items will populate the
INTERFACE_SOURCES <#prop_tgt:INTERFACE_SOURCES> property of <target>,
which are used when building dependents. A target created by
add_custom_target() <#command:add_custom_target> can only have PRIVATE
scope.
Repeated calls for the same <target> append items in the order called.
Added in version 3.3: Allow exporting targets with INTERFACE_SOURCES <#
prop_tgt:INTERFACE_SOURCES>.
Added in version 3.11: Allow setting INTERFACE items on IMPORTED
targets <#imported-targets>.
Changed in version 3.13: Relative source file paths are interpreted as
being relative to the current source directory (i.e.
CMAKE_CURRENT_SOURCE_DIR <#variable:CMAKE_CURRENT_SOURCE_DIR>). See
policy CMP0076 <#policy:CMP0076>.
A path that begins with a generator expression is left unmodified.
When a target's SOURCE_DIR <#prop_tgt:SOURCE_DIR> property differs from
CMAKE_CURRENT_SOURCE_DIR <#variable:CMAKE_CURRENT_SOURCE_DIR>, use
absolute paths in generator expressions to ensure the sources are
correctly assigned to the target.
# WRONG: starts with generator expression, but relative path used
target_sources(MyTarget PRIVATE "$<$cmake-buildsystem(7) <#manual:cmake-buildsystem(7)> manual for
more on defining buildsystem properties.
File Sets
Added in version 3.23.
target_sources(<target>
[<INTERFACE|PUBLIC|PRIVATE>
[FILE_SET <set> [TYPE <type>] [BASE_DIRS <dirs>...] [FILES <files>...]]...
]...)
Adds a file set to a target, or adds files to an existing file set.
Targets have zero or more named file sets. Each file set has a name, a
type, a scope of INTERFACE, PUBLIC, or PRIVATE, one or more base
directories, and files within those directories. The acceptable types
include:
HEADERS
Sources intended to be used via a language's #include mechanism.
CXX_MODULES
Added in version 3.28.
Sources which contain C++ interface module or partition units
(i.e., those using the export keyword). This file set type may
not have an INTERFACE scope except on IMPORTED targets.
The optional default file sets are named after their type. The target
may not be a custom target or FRAMEWORK <#prop_tgt:FRAMEWORK> target.
Files in a PRIVATE or PUBLIC file set are marked as source files for
the purposes of IDE integration. Additionally, files in HEADERS file
sets have their HEADER_FILE_ONLY <#prop_sf:HEADER_FILE_ONLY> property
set to TRUE. Files in an INTERFACE or PUBLIC file set can be installed
with the install(TARGETS) <#targets> command, and exported with the
install(EXPORT) <#export> and export() <#command:export> commands.
Each target_sources(FILE_SET) entry starts with INTERFACE, PUBLIC, or
PRIVATE and accepts the following arguments:
FILE_SET <set>
The name of the file set to create or add to. It must contain only
letters, numbers and underscores. Names starting with a capital
letter are reserved for built-in file sets predefined by CMake. The
only predefined set names are those matching the acceptable types.
All other set names must not start with a capital letter or
underscore.
TYPE <type>
Every file set is associated with a particular type of file. Only
types specified above may be used and it is an error to specify
anything else. As a special case, if the name of the file set is one
of the types, the type does not need to be specified and the TYPE
<type> arguments can be omitted. For all other file set names, TYPE
is required.
BASE_DIRS <dirs>...
An optional list of base directories of the file set. Any relative
path is treated as relative to the current source directory (i.e.
CMAKE_CURRENT_SOURCE_DIR <#variable:CMAKE_CURRENT_SOURCE_DIR>). If
no BASE_DIRS are specified when the file set is first created, the
value of CMAKE_CURRENT_SOURCE_DIR <#
variable:CMAKE_CURRENT_SOURCE_DIR> is added. This argument supports
generator expressions <#manual:cmake-generator-expressions(7)>.
No two base directories for a file set may be sub-directories of
each other. This requirement must be met across all base
directories added to a file set, not just those within a single call
to target_sources().
FILES <files>...
An optional list of files to add to the file set. Each file must be
in one of the base directories, or a subdirectory of one of the base
directories. This argument supports generator expressions <#
manual:cmake-generator-expressions(7)>.
If relative paths are specified, they are considered relative to
CMAKE_CURRENT_SOURCE_DIR <#variable:CMAKE_CURRENT_SOURCE_DIR> at the
time target_sources() is called. An exception to this is a path
starting with $<. Such paths are treated as relative to the target's
source directory after evaluation of generator expressions.
The following target properties are set by target_sources(FILE_SET),
but they should not generally be manipulated directly:
For file sets of type HEADERS:
o HEADER_SETS <#prop_tgt:HEADER_SETS>
o INTERFACE_HEADER_SETS <#prop_tgt:INTERFACE_HEADER_SETS>
o HEADER_SET <#prop_tgt:HEADER_SET>
o HEADER_SET_<NAME> <#prop_tgt:HEADER_SET_<NAME>>
o HEADER_DIRS <#prop_tgt:HEADER_DIRS>
o HEADER_DIRS_<NAME> <#prop_tgt:HEADER_DIRS_<NAME>>
For file sets of type CXX_MODULES:
o CXX_MODULE_SETS <#prop_tgt:CXX_MODULE_SETS>
o INTERFACE_CXX_MODULE_SETS <#prop_tgt:INTERFACE_CXX_MODULE_SETS>
o CXX_MODULE_SET <#prop_tgt:CXX_MODULE_SET>
o CXX_MODULE_SET_<NAME> <#prop_tgt:CXX_MODULE_SET_<NAME>>
o CXX_MODULE_DIRS <#prop_tgt:CXX_MODULE_DIRS>
o CXX_MODULE_DIRS_<NAME> <#prop_tgt:CXX_MODULE_DIRS_<NAME>>
Target properties related to include directories are also modified by
target_sources(FILE_SET) as follows:
INCLUDE_DIRECTORIES <#prop_tgt:INCLUDE_DIRECTORIES>
If the TYPE is HEADERS, and the scope of the file set is PRIVATE or
PUBLIC, all of the BASE_DIRS of the file set are wrapped in
$<BUILD_INTERFACE> <#genex:BUILD_INTERFACE> and appended to this
property.
INTERFACE_INCLUDE_DIRECTORIES <#prop_tgt:INTERFACE_INCLUDE_DIRECTORIES>
If the TYPE is HEADERS, and the scope of the file set is INTERFACE
or PUBLIC, all of the BASE_DIRS of the file set are wrapped in
$<BUILD_INTERFACE> <#genex:BUILD_INTERFACE> and appended to this
property.
See Also
o add_executable() <#command:add_executable>
o add_library() <#command:add_library>
o target_compile_definitions() <#command:target_compile_definitions>
o target_compile_features() <#command:target_compile_features>
o target_compile_options() <#command:target_compile_options>
o target_include_directories() <#command:target_include_directories>
o target_link_libraries() <#command:target_link_libraries>
o target_link_directories() <#command:target_link_directories>
o target_link_options() <#command:target_link_options>
o target_precompile_headers() <#command:target_precompile_headers>
try_compile
Try building some code.
Try Compiling Whole Projects
try_compile(<compileResultVar> PROJECT <projectName>
SOURCE_DIR <srcdir>
[BINARY_DIR <bindir>]
[TARGET <targetName>]
[LOG_DESCRIPTION <text>]
[NO_CACHE]
[NO_LOG]
[CMAKE_FLAGS <flags>...]
[OUTPUT_VARIABLE <var>])
Added in version 3.25.
Try building a project. Build success returns TRUE and build failure
returns FALSE in <compileResultVar>.
In this form, <srcdir> should contain a complete CMake project with a
CMakeLists.txt file and all sources. The <bindir> and <srcdir> will
not be deleted after this command is run. Specify <targetName> to
build a specific target instead of the all or ALL_BUILD target. See
below for the meaning of other options.
Changed in version 3.24: CMake variables describing platform settings,
and those listed by the CMAKE_TRY_COMPILE_PLATFORM_VARIABLES <#
variable:CMAKE_TRY_COMPILE_PLATFORM_VARIABLES> variable, are propagated
into the project's build configuration. See policy CMP0137 <#
policy:CMP0137>. Previously this was only done by the source file
signature.
Added in version 3.26: This command records a configure-log try_compile
event <#try-compile-configure-log-event> if the NO_LOG option is not
specified.
Added in version 3.30: If the
PROPAGATE_TOP_LEVEL_INCLUDES_TO_TRY_COMPILE <#
prop_gbl:PROPAGATE_TOP_LEVEL_INCLUDES_TO_TRY_COMPILE> global property
is set to true, CMAKE_PROJECT_TOP_LEVEL_INCLUDES <#
variable:CMAKE_PROJECT_TOP_LEVEL_INCLUDES> is propagated into the
project's build configuration.
This command supports an alternate signature for CMake older than 3.25.
The signature above is recommended for clarity.
try_compile(<compileResultVar> <bindir> <srcdir>
<projectName> [<targetName>]
[CMAKE_FLAGS <flags>...]
[OUTPUT_VARIABLE <var>])
Try Compiling Source Files
try_compile(<compileResultVar>
[SOURCES_TYPE <type>]
<SOURCES <srcfile...> |
SOURCE_FROM_CONTENT <name> <content> |
SOURCE_FROM_VAR <name> <var> |
SOURCE_FROM_FILE <name> <path> >...
[LOG_DESCRIPTION <text>]
[NO_CACHE]
[NO_LOG]
[CMAKE_FLAGS <flags>...]
[COMPILE_DEFINITIONS <defs>...]
[LINK_OPTIONS <options>...]
[LINK_LIBRARIES <libs>...]
[LINKER_LANGUAGE <lang>]
[OUTPUT_VARIABLE <var>]
[COPY_FILE <fileName> [COPY_FILE_ERROR <var>]]
[<LANG>_STANDARD <std>]
[<LANG>_STANDARD_REQUIRED <bool>]
[<LANG>_EXTENSIONS <bool>]
)
Added in version 3.25.
Try building an executable or static library from one or more source
files (which one is determined by the CMAKE_TRY_COMPILE_TARGET_TYPE <#
variable:CMAKE_TRY_COMPILE_TARGET_TYPE> variable). Build success
returns TRUE and build failure returns FALSE in <compileResultVar>.
In this form, one or more source files must be provided. Additionally,
one of SOURCES and/or SOURCE_FROM_* must precede other keywords.
If CMAKE_TRY_COMPILE_TARGET_TYPE <#
variable:CMAKE_TRY_COMPILE_TARGET_TYPE> is unset or is set to
EXECUTABLE, the sources must include a definition for main and CMake
will create a CMakeLists.txt file to build the source(s) as an
executable. If CMAKE_TRY_COMPILE_TARGET_TYPE <#
variable:CMAKE_TRY_COMPILE_TARGET_TYPE> is set to STATIC_LIBRARY, a
static library will be built instead and no definition for main is
required. For an executable, the generated CMakeLists.txt file would
contain something like the following:
add_definitions(<expanded COMPILE_DEFINITIONS from caller>)
include_directories(${INCLUDE_DIRECTORIES})
link_directories(${LINK_DIRECTORIES})
add_executable(cmTryCompileExec <srcfile>...)
target_link_options(cmTryCompileExec PRIVATE <LINK_OPTIONS from caller>)
target_link_libraries(cmTryCompileExec ${LINK_LIBRARIES})
CMake automatically generates, for each try_compile operation, a unique
directory under ${CMAKE_BINARY_DIR}/CMakeFiles/CMakeScratch with an
unspecified name. These directories are cleaned automatically unless
--debug-trycompile <#cmdoption-cmake-debug-trycompile> is passed to
cmake. Such directories from previous runs are also unconditionally
cleaned at the beginning of any cmake execution.
This command supports an alternate signature for CMake older than 3.25.
The signature above is recommended for clarity.
try_compile(<compileResultVar> <bindir> <srcfile|SOURCES srcfile...>
[CMAKE_FLAGS <flags>...]
[COMPILE_DEFINITIONS <defs>...]
[LINK_OPTIONS <options>...]
[LINK_LIBRARIES <libs>...]
[OUTPUT_VARIABLE <var>]
[COPY_FILE <fileName> [COPY_FILE_ERROR <var>]]
[<LANG>_STANDARD <std>]
[<LANG>_STANDARD_REQUIRED <bool>]
[<LANG>_EXTENSIONS <bool>]
)
In this version, try_compile will use <bindir>/CMakeFiles/CMakeTmp for
its operation, and all such files will be cleaned automatically. For
debugging, --debug-trycompile <#cmdoption-cmake-debug-trycompile> can
be passed to cmake to avoid this clean. However, multiple sequential
try_compile operations, if given the same <bindir>, will reuse this
single output directory, such that you can only debug one such
try_compile call at a time. Use of the newer signature is recommended
to simplify debugging of multiple try_compile operations.
Options
The options for the above signatures are:
CMAKE_FLAGS <flags>...
Specify flags of the form -DVAR:TYPE=VALUE <#cmdoption-cmake-D>
to be passed to the cmake(1) <#manual:cmake(1)> command-line
used to drive the test build. The above example shows how
values for variables COMPILE_DEFINITIONS, INCLUDE_DIRECTORIES,
LINK_DIRECTORIES, LINK_LIBRARIES, and LINK_OPTIONS are used.
Compiler options can be passed in like CMAKE_FLAGS
-DCOMPILE_DEFINITIONS=-Werror.
COMPILE_DEFINITIONS <defs>...
Specify -Ddefinition arguments to pass to add_definitions() <#
command:add_definitions> in the generated test project.
COPY_FILE <fileName>
Copy the built executable or static library to the given
<fileName>.
COPY_FILE_ERROR <var>
Use after COPY_FILE to capture into variable <var> any error
message encountered while trying to copy the file.
LINK_LIBRARIES <libs>...
Specify libraries to be linked in the generated project. The
list of libraries may refer to system libraries and to Imported
Targets <#imported-targets> from the calling project.
If this option is specified, any -DLINK_LIBRARIES=... value
given to the CMAKE_FLAGS option will be ignored.
Added in version 3.29: Alias targets to imported libraries are
also supported.
LINK_OPTIONS <options>...
Added in version 3.14.
Specify link step options to pass to target_link_options() <#
command:target_link_options> or to set the
STATIC_LIBRARY_OPTIONS <#prop_tgt:STATIC_LIBRARY_OPTIONS> target
property in the generated project, depending on the
CMAKE_TRY_COMPILE_TARGET_TYPE <#
variable:CMAKE_TRY_COMPILE_TARGET_TYPE> variable.
LINKER_LANGUAGE <lang>
Added in version 3.29.
Specify the LINKER_LANGUAGE <#prop_tgt:LINKER_LANGUAGE> target
property of the generated project. When using multiple source
files with different languages, set this to the language of the
source file containing the program entry point, e.g., main.
LOG_DESCRIPTION <text>
Added in version 3.26.
Specify a non-empty text description of the purpose of the
check. This is recorded in the cmake-configure-log(7) <#
manual:cmake-configure-log(7)> entry.
NO_CACHE
Added in version 3.25.
The result will be stored in a normal variable rather than a
cache entry.
The result variable is normally cached so that a simple pattern
can be used to avoid repeating the test on subsequent executions
of CMake:
if(NOT DEFINED RESULTVAR)
# ...(check-specific setup code)...
try_compile(RESULTVAR ...)
# ...(check-specific logging and cleanup code)...
endif()
If the guard variable and result variable are not the same (for
example, if the test is part of a larger inspection), NO_CACHE
may be useful to avoid leaking the intermediate result variable
into the cache.
NO_LOG Added in version 3.26.
Do not record a cmake-configure-log(7) <#manual:cmake-configure-
log(7)> entry for this call.
OUTPUT_VARIABLE <var>
Store the output from the build process in the given variable.
SOURCE_FROM_CONTENT <name> <content>
Added in version 3.25.
Write <content> to a file named <name> in the operation
directory. This can be used to bypass the need to separately
write a source file when the contents of the file are
dynamically specified. The specified <name> is not allowed to
contain path components.
SOURCE_FROM_CONTENT may be specified multiple times.
SOURCE_FROM_FILE <name> <path>
Added in version 3.25.
Copy <path> to a file named <name> in the operation directory.
This can be used to consolidate files into the operation
directory, which may be useful if a source which already exists
(i.e. as a stand-alone file in a project's source repository)
needs to refer to other file(s) created by SOURCE_FROM_*.
(Otherwise, SOURCES is usually more convenient.) The specified
<name> is not allowed to contain path components.
SOURCE_FROM_VAR <name> <var>
Added in version 3.25.
Write the contents of <var> to a file named <name> in the
operation directory. This is the same as SOURCE_FROM_CONTENT,
but takes the contents from the specified CMake variable, rather
than directly, which may be useful when passing arguments
through a function which wraps try_compile. The specified <name>
is not allowed to contain path components.
SOURCE_FROM_VAR may be specified multiple times.
SOURCES_TYPE <type>
Added in version 3.28.
Sources may be classified using the SOURCES_TYPE argument. Once
specified, all subsequent sources specified will be treated as
that type until another SOURCES_TYPE is given. Available types
are:
NORMAL Sources are not added to any FILE_SET in the generated
project.
CXX_MODULE
Added in version 3.28.
Sources are added to a FILE_SET of type CXX_MODULES in
the generated project.
The default type of sources is NORMAL.
<LANG>_STANDARD <std>
Added in version 3.8.
Specify the C_STANDARD <#prop_tgt:C_STANDARD>, CXX_STANDARD <#
prop_tgt:CXX_STANDARD>, OBJC_STANDARD <#prop_tgt:OBJC_STANDARD>,
OBJCXX_STANDARD <#prop_tgt:OBJCXX_STANDARD>, or CUDA_STANDARD <#
prop_tgt:CUDA_STANDARD> target property of the generated
project.
<LANG>_STANDARD_REQUIRED <bool>
Added in version 3.8.
Specify the C_STANDARD_REQUIRED <#prop_tgt:C_STANDARD_REQUIRED>,
CXX_STANDARD_REQUIRED <#prop_tgt:CXX_STANDARD_REQUIRED>,
OBJC_STANDARD_REQUIRED <#prop_tgt:OBJC_STANDARD_REQUIRED>,
OBJCXX_STANDARD_REQUIRED <#prop_tgt:OBJCXX_STANDARD_REQUIRED>,or
CUDA_STANDARD_REQUIRED <#prop_tgt:CUDA_STANDARD_REQUIRED> target
property of the generated project.
<LANG>_EXTENSIONS <bool>
Added in version 3.8.
Specify the C_EXTENSIONS <#prop_tgt:C_EXTENSIONS>,
CXX_EXTENSIONS <#prop_tgt:CXX_EXTENSIONS>, OBJC_EXTENSIONS <#
prop_tgt:OBJC_EXTENSIONS>, OBJCXX_EXTENSIONS <#
prop_tgt:OBJCXX_EXTENSIONS>, or CUDA_EXTENSIONS <#
prop_tgt:CUDA_EXTENSIONS> target property of the generated
project.
Other Behavior Settings
Added in version 3.4: If set, the following variables are passed in to
the generated try_compile CMakeLists.txt to initialize compile target
properties with default values:
o CMAKE_CUDA_RUNTIME_LIBRARY <#variable:CMAKE_CUDA_RUNTIME_LIBRARY>
o CMAKE_ENABLE_EXPORTS <#variable:CMAKE_ENABLE_EXPORTS>
o CMAKE_LINK_SEARCH_START_STATIC <#
variable:CMAKE_LINK_SEARCH_START_STATIC>
o CMAKE_LINK_SEARCH_END_STATIC <#variable:CMAKE_LINK_SEARCH_END_STATIC>
o CMAKE_MSVC_RUNTIME_LIBRARY <#variable:CMAKE_MSVC_RUNTIME_LIBRARY>
o CMAKE_POSITION_INDEPENDENT_CODE <#
variable:CMAKE_POSITION_INDEPENDENT_CODE>
o CMAKE_WATCOM_RUNTIME_LIBRARY <#variable:CMAKE_WATCOM_RUNTIME_LIBRARY>
If CMP0056 <#policy:CMP0056> is set to NEW, then CMAKE_EXE_LINKER_FLAGS
<#variable:CMAKE_EXE_LINKER_FLAGS> is passed in as well.
Changed in version 3.14: If CMP0083 <#policy:CMP0083> is set to NEW,
then in order to obtain correct behavior at link time, the
check_pie_supported() command from the CheckPIESupported <#
module:CheckPIESupported> module must be called before using the
try_compile command.
The current settings of CMP0065 <#policy:CMP0065> and CMP0083 <#
policy:CMP0083> are propagated through to the generated test project.
Set variable CMAKE_TRY_COMPILE_CONFIGURATION <#
variable:CMAKE_TRY_COMPILE_CONFIGURATION> to choose a build
configuration:
o For multi-config generators, this selects which configuration to
build.
o For single-config generators, this sets CMAKE_BUILD_TYPE <#
variable:CMAKE_BUILD_TYPE> in the test project.
Added in version 3.6: Set the CMAKE_TRY_COMPILE_TARGET_TYPE <#
variable:CMAKE_TRY_COMPILE_TARGET_TYPE> variable to specify the type of
target used for the source file signature.
Added in version 3.6: Set the CMAKE_TRY_COMPILE_PLATFORM_VARIABLES <#
variable:CMAKE_TRY_COMPILE_PLATFORM_VARIABLES> variable to specify
variables that must be propagated into the test project. This variable
is meant for use only in toolchain files and is only honored by the
try_compile() command for the source files form, not when given a whole
project.
Changed in version 3.8: If CMP0067 <#policy:CMP0067> is set to NEW, or
any of the <LANG>_STANDARD, <LANG>_STANDARD_REQUIRED, or
<LANG>_EXTENSIONS options are used, then the language standard
variables are honored:
o CMAKE_C_STANDARD <#variable:CMAKE_C_STANDARD>
o CMAKE_C_STANDARD_REQUIRED <#variable:CMAKE_C_STANDARD_REQUIRED>
o CMAKE_C_EXTENSIONS <#variable:CMAKE_C_EXTENSIONS>
o CMAKE_CXX_STANDARD <#variable:CMAKE_CXX_STANDARD>
o CMAKE_CXX_STANDARD_REQUIRED <#variable:CMAKE_CXX_STANDARD_REQUIRED>
o CMAKE_CXX_EXTENSIONS <#variable:CMAKE_CXX_EXTENSIONS>
o CMAKE_OBJC_STANDARD <#variable:CMAKE_OBJC_STANDARD>
o CMAKE_OBJC_STANDARD_REQUIRED <#variable:CMAKE_OBJC_STANDARD_REQUIRED>
o CMAKE_OBJC_EXTENSIONS <#variable:CMAKE_OBJC_EXTENSIONS>
o CMAKE_OBJCXX_STANDARD <#variable:CMAKE_OBJCXX_STANDARD>
o CMAKE_OBJCXX_STANDARD_REQUIRED <#
variable:CMAKE_OBJCXX_STANDARD_REQUIRED>
o CMAKE_OBJCXX_EXTENSIONS <#variable:CMAKE_OBJCXX_EXTENSIONS>
o CMAKE_CUDA_STANDARD <#variable:CMAKE_CUDA_STANDARD>
o CMAKE_CUDA_STANDARD_REQUIRED <#variable:CMAKE_CUDA_STANDARD_REQUIRED>
o CMAKE_CUDA_EXTENSIONS <#variable:CMAKE_CUDA_EXTENSIONS>
Their values are used to set the corresponding target properties in the
generated project (unless overridden by an explicit option).
Changed in version 3.14: For the Green Hills MULTI <#generator:Green
Hills MULTI> generator, the GHS toolset and target system customization
cache variables are also propagated into the test project.
Added in version 3.24: The CMAKE_TRY_COMPILE_NO_PLATFORM_VARIABLES <#
variable:CMAKE_TRY_COMPILE_NO_PLATFORM_VARIABLES> variable may be set
to disable passing platform variables into the test project.
Added in version 3.25: If CMP0141 <#policy:CMP0141> is set to NEW, one
can use CMAKE_MSVC_DEBUG_INFORMATION_FORMAT <#
variable:CMAKE_MSVC_DEBUG_INFORMATION_FORMAT> to specify the MSVC debug
information format.
Added in version 3.30: If the
PROPAGATE_TOP_LEVEL_INCLUDES_TO_TRY_COMPILE <#
prop_gbl:PROPAGATE_TOP_LEVEL_INCLUDES_TO_TRY_COMPILE> global property
is set to true, CMAKE_PROJECT_TOP_LEVEL_INCLUDES <#
variable:CMAKE_PROJECT_TOP_LEVEL_INCLUDES> is propagated into the test
project's build configuration when using the whole-project signature.
See Also
o try_run() <#command:try_run>
try_run
Try compiling and then running some code.
Try Compiling and Running Source Files
try_run(<runResultVar> <compileResultVar>
[SOURCES_TYPE <type>]
<SOURCES <srcfile...> |
SOURCE_FROM_CONTENT <name> <content> |
SOURCE_FROM_VAR <name> <var> |
SOURCE_FROM_FILE <name> <path> >...
[LOG_DESCRIPTION <text>]
[NO_CACHE]
[NO_LOG]
[CMAKE_FLAGS <flags>...]
[COMPILE_DEFINITIONS <defs>...]
[LINK_OPTIONS <options>...]
[LINK_LIBRARIES <libs>...]
[COMPILE_OUTPUT_VARIABLE <var>]
[COPY_FILE <fileName> [COPY_FILE_ERROR <var>]]
[<LANG>_STANDARD <std>]
[<LANG>_STANDARD_REQUIRED <bool>]
[<LANG>_EXTENSIONS <bool>]
[RUN_OUTPUT_VARIABLE <var>]
[RUN_OUTPUT_STDOUT_VARIABLE <var>]
[RUN_OUTPUT_STDERR_VARIABLE <var>]
[WORKING_DIRECTORY <var>]
[ARGS <args>...]
)
Added in version 3.25.
Try building an executable from one or more source files. Build
success returns TRUE and build failure returns FALSE in
<compileResultVar>. If the build succeeds, this runs the executable
and stores the exit code in <runResultVar>. If the executable was
built, but failed to run, then <runResultVar> will be set to
FAILED_TO_RUN. See command try_compile() <#command:try_compile> for
documentation of options common to both commands, and for information
on how the test project is constructed to build the source file.
One or more source files must be provided. Additionally, one of SOURCES
and/or SOURCE_FROM_* must precede other keywords.
Added in version 3.26: This command records a configure-log try_run
event <#try-run-configure-log-event> if the NO_LOG option is not
specified.
This command supports an alternate signature for CMake older than 3.25.
The signature above is recommended for clarity.
try_run(<runResultVar> <compileResultVar>
<bindir> <srcfile|SOURCES srcfile...>
[CMAKE_FLAGS <flags>...]
[COMPILE_DEFINITIONS <defs>...]
[LINK_OPTIONS <options>...]
[LINK_LIBRARIES <libs>...]
[LINKER_LANGUAGE <lang>]
[COMPILE_OUTPUT_VARIABLE <var>]
[COPY_FILE <fileName> [COPY_FILE_ERROR <var>]]
[<LANG>_STANDARD <std>]
[<LANG>_STANDARD_REQUIRED <bool>]
[<LANG>_EXTENSIONS <bool>]
[RUN_OUTPUT_VARIABLE <var>]
[OUTPUT_VARIABLE <var>]
[WORKING_DIRECTORY <var>]
[ARGS <args>...]
)
Options
The options specific to try_run are:
COMPILE_OUTPUT_VARIABLE <var>
Report the compile step build output in a given variable.
OUTPUT_VARIABLE <var>
Report the compile build output and the output from running the
executable in the given variable. This option exists for legacy
reasons and is only supported by the old try_run signature.
Prefer COMPILE_OUTPUT_VARIABLE and RUN_OUTPUT_VARIABLE instead.
RUN_OUTPUT_VARIABLE <var>
Report the output from running the executable in a given
variable.
RUN_OUTPUT_STDOUT_VARIABLE <var>
Added in version 3.25.
Report the output of stdout from running the executable in a
given variable.
RUN_OUTPUT_STDERR_VARIABLE <var>
Added in version 3.25.
Report the output of stderr from running the executable in a
given variable.
WORKING_DIRECTORY <var>
Added in version 3.20.
Run the executable in the given directory. If no
WORKING_DIRECTORY is specified, the executable will run in
<bindir> or the current build directory.
ARGS <args>...
Additional arguments to pass to the executable when running it.
Other Behavior Settings
Set variable CMAKE_TRY_COMPILE_CONFIGURATION <#
variable:CMAKE_TRY_COMPILE_CONFIGURATION> to choose a build
configuration:
o For multi-config generators, this selects which configuration to
build.
o For single-config generators, this sets CMAKE_BUILD_TYPE <#
variable:CMAKE_BUILD_TYPE> in the test project.
Behavior when Cross Compiling
Added in version 3.3: Use CMAKE_CROSSCOMPILING_EMULATOR when running
cross-compiled binaries.
When cross compiling, the executable compiled in the first step usually
cannot be run on the build host. The try_run command checks the
CMAKE_CROSSCOMPILING <#variable:CMAKE_CROSSCOMPILING> variable to
detect whether CMake is in cross-compiling mode. If that is the case,
it will still try to compile the executable, but it will not try to run
the executable unless the CMAKE_CROSSCOMPILING_EMULATOR <#
variable:CMAKE_CROSSCOMPILING_EMULATOR> variable is set. Instead it
will create cache variables which must be filled by the user or by
presetting them in some CMake script file to the values the executable
would have produced if it had been run on its actual target platform.
These cache entries are:
<runResultVar>
Exit code if the executable were to be run on the target
platform.
<runResultVar>__TRYRUN_OUTPUT
Output from stdout and stderr if the executable were to be run
on the target platform. This is created only if the
RUN_OUTPUT_VARIABLE or OUTPUT_VARIABLE option was used.
In order to make cross compiling your project easier, use try_run only
if really required. If you use try_run, use the
RUN_OUTPUT_STDOUT_VARIABLE, RUN_OUTPUT_STDERR_VARIABLE,
RUN_OUTPUT_VARIABLE or OUTPUT_VARIABLE options only if really required.
Using them will require that when cross-compiling, the cache variables
will have to be set manually to the output of the executable. You can
also "guard" the calls to try_run with an if() <#command:if> block
checking the CMAKE_CROSSCOMPILING <#variable:CMAKE_CROSSCOMPILING>
variable and provide an easy-to-preset alternative for this case.
CTEST COMMANDS
These commands are available only in CTest scripts.
ctest_build
Perform the CTest Build Step <#ctest-build-step> as a Dashboard Client
<#dashboard-client>.
ctest_build([BUILD <build-dir>] [APPEND]
[CONFIGURATION <config>]
[PARALLEL_LEVEL <parallel>]
[FLAGS <flags>]
[PROJECT_NAME <project-name>]
[TARGET <target-name>]
[NUMBER_ERRORS <num-err-var>]
[NUMBER_WARNINGS <num-warn-var>]
[RETURN_VALUE <result-var>]
[CAPTURE_CMAKE_ERROR <result-var>]
)
Build the project and store results in Build.xml for submission with
the ctest_submit() <#command:ctest_submit> command.
The CTEST_BUILD_COMMAND <#variable:CTEST_BUILD_COMMAND> variable may be
set to explicitly specify the build command line. Otherwise the build
command line is computed automatically based on the options given.
The options are:
BUILD <build-dir>
Specify the top-level build directory. If not given, the
CTEST_BINARY_DIRECTORY <#variable:CTEST_BINARY_DIRECTORY>
variable is used.
APPEND Mark Build.xml for append to results previously submitted to a
dashboard server since the last ctest_start() <#
command:ctest_start> call. Append semantics are defined by the
dashboard server in use. This does not cause results to be
appended to a .xml file produced by a previous call to this
command.
CONFIGURATION <config>
Specify the build configuration (e.g. Debug). If not specified
the CTEST_BUILD_CONFIGURATION variable will be checked.
Otherwise the -C <cfg> <#cmdoption-ctest-C> option given to the
ctest(1) <#manual:ctest(1)> command will be used, if any.
PARALLEL_LEVEL <parallel>
Added in version 3.21.
Specify the parallel level of the underlying build system. If
not specified, the CMAKE_BUILD_PARALLEL_LEVEL <#
envvar:CMAKE_BUILD_PARALLEL_LEVEL> environment variable will be
checked.
FLAGS <flags>
Pass additional arguments to the underlying build command. If
not specified the CTEST_BUILD_FLAGS variable will be checked.
This can, e.g., be used to trigger a parallel build using the -j
option of make. See the ProcessorCount <#module:ProcessorCount>
module for an example.
PROJECT_NAME <project-name>
Ignored since CMake 3.0.
Changed in version 3.14: This value is no longer required.
TARGET <target-name>
Specify the name of a target to build. If not specified the
CTEST_BUILD_TARGET variable will be checked. Otherwise the
default target will be built. This is the "all" target (called
ALL_BUILD in Visual Studio Generators <#visual-studio-
generators>).
NUMBER_ERRORS <num-err-var>
Store the number of build errors detected in the given variable.
NUMBER_WARNINGS <num-warn-var>
Store the number of build warnings detected in the given
variable.
RETURN_VALUE <result-var>
Store the return value of the native build tool in the given
variable.
CAPTURE_CMAKE_ERROR <result-var>
Added in version 3.7.
Store in the <result-var> variable -1 if there are any errors
running the command and prevent ctest from returning non-zero if
an error occurs.
QUIET Added in version 3.3.
Suppress any CTest-specific non-error output that would have
been printed to the console otherwise. The summary of warnings
/ errors, as well as the output from the native build tool is
unaffected by this option.
ctest_configure
Perform the CTest Configure Step <#ctest-configure-step> as a Dashboard
Client <#dashboard-client>.
ctest_configure([BUILD <build-dir>] [SOURCE <source-dir>] [APPEND]
[OPTIONS <options>] [RETURN_VALUE <result-var>] [QUIET]
[CAPTURE_CMAKE_ERROR <result-var>])
Configure the project build tree and record results in Configure.xml
for submission with the ctest_submit() <#command:ctest_submit> command.
The options are:
BUILD <build-dir>
Specify the top-level build directory. If not given, the
CTEST_BINARY_DIRECTORY <#variable:CTEST_BINARY_DIRECTORY>
variable is used.
SOURCE <source-dir>
Specify the source directory. If not given, the
CTEST_SOURCE_DIRECTORY <#variable:CTEST_SOURCE_DIRECTORY>
variable is used.
APPEND Mark Configure.xml for append to results previously submitted to
a dashboard server since the last ctest_start() <#
command:ctest_start> call. Append semantics are defined by the
dashboard server in use. This does not cause results to be
appended to a .xml file produced by a previous call to this
command.
OPTIONS <options>
Specify command-line arguments to pass to the configuration
tool.
RETURN_VALUE <result-var>
Store in the <result-var> variable the return value of the
native configuration tool.
CAPTURE_CMAKE_ERROR <result-var>
Added in version 3.7.
Store in the <result-var> variable -1 if there are any errors
running the command and prevent ctest from returning non-zero if
an error occurs.
QUIET Added in version 3.3.
Suppress any CTest-specific non-error messages that would have
otherwise been printed to the console. Output from the
underlying configure command is not affected.
ctest_coverage
Perform the CTest Coverage Step <#ctest-coverage-step> as a Dashboard
Client <#dashboard-client>.
ctest_coverage([BUILD <build-dir>] [APPEND]
[LABELS <label>...]
[RETURN_VALUE <result-var>]
[CAPTURE_CMAKE_ERROR <result-var>]
[QUIET]
)
Collect coverage tool results and stores them in Coverage.xml for
submission with the ctest_submit() <#command:ctest_submit> command.
The options are:
BUILD <build-dir>
Specify the top-level build directory. If not given, the
CTEST_BINARY_DIRECTORY <#variable:CTEST_BINARY_DIRECTORY>
variable is used.
APPEND Mark Coverage.xml for append to results previously submitted to
a dashboard server since the last ctest_start() <#
command:ctest_start> call. Append semantics are defined by the
dashboard server in use. This does not cause results to be
appended to a .xml file produced by a previous call to this
command.
LABELS Filter the coverage report to include only source files labeled
with at least one of the labels specified.
RETURN_VALUE <result-var>
Store in the <result-var> variable 0 if coverage tools ran
without error and non-zero otherwise.
CAPTURE_CMAKE_ERROR <result-var>
Added in version 3.7.
Store in the <result-var> variable -1 if there are any errors
running the command and prevent ctest from returning non-zero if
an error occurs.
QUIET Added in version 3.3.
Suppress any CTest-specific non-error output that would have
been printed to the console otherwise. The summary indicating
how many lines of code were covered is unaffected by this
option.
ctest_empty_binary_directory
empties the binary directory
ctest_empty_binary_directory(<directory>)
Removes a binary directory. This command will perform some checks
prior to deleting the directory in an attempt to avoid malicious or
accidental directory deletion.
ctest_memcheck
Perform the CTest MemCheck Step <#ctest-memcheck-step> as a Dashboard
Client <#dashboard-client>.
ctest_memcheck([BUILD <build-dir>] [APPEND]
[START <start-number>]
[END <end-number>]
[STRIDE <stride-number>]
[EXCLUDE <exclude-regex>]
[INCLUDE <include-regex>]
[EXCLUDE_LABEL <label-exclude-regex>]
[INCLUDE_LABEL <label-include-regex>]
[EXCLUDE_FIXTURE <regex>]
[EXCLUDE_FIXTURE_SETUP <regex>]
[EXCLUDE_FIXTURE_CLEANUP <regex>]
[PARALLEL_LEVEL <level>]
[RESOURCE_SPEC_FILE <file>]
[TEST_LOAD <threshold>]
[SCHEDULE_RANDOM <ON|OFF>]
[STOP_ON_FAILURE]
[STOP_TIME <time-of-day>]
[RETURN_VALUE <result-var>]
[CAPTURE_CMAKE_ERROR <result-var>]
[REPEAT <mode>:<n>]
[OUTPUT_JUNIT <file>]
[DEFECT_COUNT <defect-count-var>]
[QUIET]
)
Run tests with a dynamic analysis tool and store results in
MemCheck.xml for submission with the ctest_submit() <#
command:ctest_submit> command.
Most options are the same as those for the ctest_test() <#
command:ctest_test> command.
The options unique to this command are:
DEFECT_COUNT <defect-count-var>
Added in version 3.8.
Store in the <defect-count-var> the number of defects found.
ctest_read_custom_files
read CTestCustom files.
ctest_read_custom_files(<directory>...)
Read all the CTestCustom.ctest or CTestCustom.cmake files from the
given directory.
By default, invoking ctest(1) <#manual:ctest(1)> without a script will
read custom files from the binary directory.
ctest_run_script
runs a ctest -S <#cmdoption-ctest-S> script
ctest_run_script([NEW_PROCESS] script_file_name script_file_name1
script_file_name2 ... [RETURN_VALUE var])
Runs a script or scripts much like if it was run from ctest -S <#
cmdoption-ctest-S>. If no argument is provided then the current script
is run using the current settings of the variables. If NEW_PROCESS is
specified then each script will be run in a separate process.If
RETURN_VALUE is specified the return value of the last script run will
be put into var.
ctest_sleep
sleeps for some amount of time
ctest_sleep(<seconds>)
Sleep for given number of seconds.
ctest_sleep(<time1> <duration> <time2>)
Sleep for t=(time1 + duration - time2) seconds if t > 0.
ctest_start
Starts the testing for a given model
ctest_start(<model> [<source> [<binary>]] [GROUP <group>] [QUIET])
ctest_start([<model> [<source> [<binary>]]] [GROUP <group>] APPEND [QUIET])
Starts the testing for a given model. The command should be called
after the binary directory is initialized.
The parameters are as follows:
<model>
Set the dashboard model. Must be one of Experimental,
Continuous, or Nightly. This parameter is required unless APPEND
is specified.
<source>
Set the source directory. If not specified, the value of
CTEST_SOURCE_DIRECTORY <#variable:CTEST_SOURCE_DIRECTORY> is
used instead.
<binary>
Set the binary directory. If not specified, the value of
CTEST_BINARY_DIRECTORY <#variable:CTEST_BINARY_DIRECTORY> is
used instead.
GROUP <group>
If GROUP is used, the submissions will go to the specified group
on the CDash server. If no GROUP is specified, the name of the
model is used by default.
Changed in version 3.16: This replaces the deprecated option
TRACK. Despite the name change its behavior is unchanged.
APPEND If APPEND is used, the existing TAG is used rather than creating
a new one based on the current time stamp. If you use APPEND,
you can omit the <model> and GROUP <group> parameters, because
they will be read from the generated TAG file. For example:
ctest_start(Experimental GROUP GroupExperimental)
Later, in another ctest -S <#cmdoption-ctest-S> script:
ctest_start(APPEND)
When the second script runs ctest_start(APPEND), it will read
the Experimental model and GroupExperimental group from the TAG
file generated by the first ctest_start() command. Please note
that if you call ctest_start(APPEND) and specify a different
model or group than in the first ctest_start() command, a
warning will be issued, and the new model and group will be
used.
QUIET Added in version 3.3.
If QUIET is used, CTest will suppress any non-error messages
that it otherwise would have printed to the console.
The parameters for ctest_start() can be issued in any order, with the
exception that <model>, <source>, and <binary> have to appear in that
order with respect to each other. The following are all valid and
equivalent:
ctest_start(Experimental path/to/source path/to/binary GROUP SomeGroup QUIET APPEND)
ctest_start(GROUP SomeGroup Experimental QUIET path/to/source APPEND path/to/binary)
ctest_start(APPEND QUIET Experimental path/to/source GROUP SomeGroup path/to/binary)
However, for the sake of readability, it is recommended that you order
your parameters in the order listed at the top of this page.
If the CTEST_CHECKOUT_COMMAND <#variable:CTEST_CHECKOUT_COMMAND>
variable (or the CTEST_CVS_CHECKOUT <#variable:CTEST_CVS_CHECKOUT>
variable) is set, its content is treated as command-line. The command
is invoked with the current working directory set to the parent of the
source directory, even if the source directory already exists. This
can be used to create the source tree from a version control
repository.
ctest_submit
Perform the CTest Submit Step <#ctest-submit-step> as a Dashboard
Client <#dashboard-client>.
ctest_submit([PARTS <part>...] [FILES <file>...]
[SUBMIT_URL <url>]
[BUILD_ID <result-var>]
[HTTPHEADER <header>]
[RETRY_COUNT <count>]
[RETRY_DELAY <delay>]
[RETURN_VALUE <result-var>]
[CAPTURE_CMAKE_ERROR <result-var>]
[QUIET]
)
Submit results to a dashboard server. By default all available parts
are submitted.
The options are:
PARTS <part>...
Specify a subset of parts to submit. Valid part names are:
Start = nothing
Update = ctest_update results, in Update.xml
Configure = ctest_configure results, in Configure.xml
Build = ctest_build results, in Build.xml
Test = ctest_test results, in Test.xml
Coverage = ctest_coverage results, in Coverage.xml
MemCheck = ctest_memcheck results, in DynamicAnalysis.xml and
DynamicAnalysis-Test.xml
Notes = Files listed by CTEST_NOTES_FILES, in Notes.xml
ExtraFiles = Files listed by CTEST_EXTRA_SUBMIT_FILES
Upload = Files prepared for upload by ctest_upload(), in Upload.xml
Submit = nothing
Done = Build is complete, in Done.xml
FILES <file>...
Specify an explicit list of specific files to be submitted.
Each individual file must exist at the time of the call.
SUBMIT_URL <url>
Added in version 3.14.
The http or https URL of the dashboard server to send the
submission to. If not given, the CTEST_SUBMIT_URL <#
variable:CTEST_SUBMIT_URL> variable is used.
BUILD_ID <result-var>
Added in version 3.15.
Store in the <result-var> variable the ID assigned to this build
by CDash.
HTTPHEADER <HTTP-header>
Added in version 3.9.
Specify HTTP header to be included in the request to CDash
during submission. For example, CDash can be configured to only
accept submissions from authenticated clients. In this case, you
should provide a bearer token in your header:
ctest_submit(HTTPHEADER "Authorization: Bearer <auth-token>")
This suboption can be repeated several times for multiple
headers.
RETRY_COUNT <count>
Specify how many times to retry a timed-out submission.
RETRY_DELAY <delay>
Specify how long (in seconds) to wait after a timed-out
submission before attempting to re-submit.
RETURN_VALUE <result-var>
Store in the <result-var> variable 0 for success and non-zero on
failure.
CAPTURE_CMAKE_ERROR <result-var>
Added in version 3.13.
Store in the <result-var> variable -1 if there are any errors
running the command and prevent ctest from returning non-zero if
an error occurs.
QUIET Added in version 3.3.
Suppress all non-error messages that would have otherwise been
printed to the console.
Submit to CDash Upload API
Added in version 3.2.
ctest_submit(CDASH_UPLOAD <file> [CDASH_UPLOAD_TYPE <type>]
[SUBMIT_URL <url>]
[BUILD_ID <result-var>]
[HTTPHEADER <header>]
[RETRY_COUNT <count>]
[RETRY_DELAY <delay>]
[RETURN_VALUE <result-var>]
[QUIET])
This second signature is used to upload files to CDash via the CDash
file upload API. The API first sends a request to upload to CDash along
with a content hash of the file. If CDash does not already have the
file, then it is uploaded. Along with the file, a CDash type string is
specified to tell CDash which handler to use to process the data.
This signature interprets options in the same way as the first one.
Added in version 3.8: Added the RETRY_COUNT, RETRY_DELAY, QUIET
options.
Added in version 3.9: Added the HTTPHEADER option.
Added in version 3.13: Added the RETURN_VALUE option.
Added in version 3.14: Added the SUBMIT_URL option.
Added in version 3.15: Added the BUILD_ID option.
ctest_test
Perform the CTest Test Step <#ctest-test-step> as a Dashboard Client <#
dashboard-client>.
ctest_test([BUILD <build-dir>] [APPEND]
[START <start-number>]
[END <end-number>]
[STRIDE <stride-number>]
[EXCLUDE <exclude-regex>]
[INCLUDE <include-regex>]
[EXCLUDE_LABEL <label-exclude-regex>]
[INCLUDE_LABEL <label-include-regex>]
[EXCLUDE_FROM_FILE <filename>]
[INCLUDE_FROM_FILE <filename>]
[EXCLUDE_FIXTURE <regex>]
[EXCLUDE_FIXTURE_SETUP <regex>]
[EXCLUDE_FIXTURE_CLEANUP <regex>]
[PARALLEL_LEVEL [<level>]]
[RESOURCE_SPEC_FILE <file>]
[TEST_LOAD <threshold>]
[SCHEDULE_RANDOM <ON|OFF>]
[STOP_ON_FAILURE]
[STOP_TIME <time-of-day>]
[RETURN_VALUE <result-var>]
[CAPTURE_CMAKE_ERROR <result-var>]
[REPEAT <mode>:<n>]
[OUTPUT_JUNIT <file>]
[QUIET]
)
Run tests in the project build tree and store results in Test.xml for
submission with the ctest_submit() <#command:ctest_submit> command.
The options are:
BUILD <build-dir>
Specify the top-level build directory. If not given, the
CTEST_BINARY_DIRECTORY <#variable:CTEST_BINARY_DIRECTORY>
variable is used.
APPEND Mark Test.xml for append to results previously submitted to a
dashboard server since the last ctest_start() <#
command:ctest_start> call. Append semantics are defined by the
dashboard server in use. This does not cause results to be
appended to a .xml file produced by a previous call to this
command.
START <start-number>
Specify the beginning of a range of test numbers.
END <end-number>
Specify the end of a range of test numbers.
STRIDE <stride-number>
Specify the stride by which to step across a range of test
numbers.
EXCLUDE <exclude-regex>
Specify a regular expression matching test names to exclude.
INCLUDE <include-regex>
Specify a regular expression matching test names to include.
Tests not matching this expression are excluded.
EXCLUDE_LABEL <label-exclude-regex>
Specify a regular expression matching test labels to exclude.
INCLUDE_LABEL <label-include-regex>
Specify a regular expression matching test labels to include.
Tests not matching this expression are excluded.
EXCLUDE_FROM_FILE <filename>
Added in version 3.29.
Do NOT run tests listed with their exact name in the given file.
INCLUDE_FROM_FILE <filename>
Added in version 3.29.
Only run the tests listed with their exact name in the given
file.
EXCLUDE_FIXTURE <regex>
Added in version 3.7.
If a test in the set of tests to be executed requires a
particular fixture, that fixture's setup and cleanup tests would
normally be added to the test set automatically. This option
prevents adding setup or cleanup tests for fixtures matching the
<regex>. Note that all other fixture behavior is retained,
including test dependencies and skipping tests that have fixture
setup tests that fail.
EXCLUDE_FIXTURE_SETUP <regex>
Added in version 3.7.
Same as EXCLUDE_FIXTURE except only matching setup tests are
excluded.
EXCLUDE_FIXTURE_CLEANUP <regex>
Added in version 3.7.
Same as EXCLUDE_FIXTURE except only matching cleanup tests are
excluded.
PARALLEL_LEVEL [<level>]
Run tests in parallel, limited to a given level of parallelism.
Added in version 3.29: The <level> may be omitted, or 0, to let
ctest use a default level of parallelism, or unbounded
parallelism, respectively, as documented by the ctest --parallel
<#cmdoption-ctest-j> option.
RESOURCE_SPEC_FILE <file>
Added in version 3.16.
Specify a resource specification file <#ctest-resource-
specification-file>. See Resource Allocation <#ctest-resource-
allocation> for more information.
TEST_LOAD <threshold>
Added in version 3.4.
While running tests in parallel, try not to start tests when
they may cause the CPU load to pass above a given threshold. If
not specified the CTEST_TEST_LOAD <#variable:CTEST_TEST_LOAD>
variable will be checked, and then the --test-load <#cmdoption-
ctest-test-load> command-line argument to ctest(1) <#
manual:ctest(1)>. See also the TestLoad setting in the CTest
Test Step <#ctest-test-step>.
REPEAT <mode>:<n>
Added in version 3.17.
Run tests repeatedly based on the given <mode> up to <n> times.
The modes are:
UNTIL_FAIL
Require each test to run <n> times without failing in
order to pass. This is useful in finding sporadic
failures in test cases.
UNTIL_PASS
Allow each test to run up to <n> times in order to pass.
Repeats tests if they fail for any reason. This is
useful in tolerating sporadic failures in test cases.
AFTER_TIMEOUT
Allow each test to run up to <n> times in order to pass.
Repeats tests only if they timeout. This is useful in
tolerating sporadic timeouts in test cases on busy
machines.
SCHEDULE_RANDOM <ON|OFF>
Launch tests in a random order. This may be useful for
detecting implicit test dependencies.
STOP_ON_FAILURE
Added in version 3.18.
Stop the execution of the tests once one has failed.
STOP_TIME <time-of-day>
Specify a time of day at which the tests should all stop
running.
RETURN_VALUE <result-var>
Store in the <result-var> variable 0 if all tests passed. Store
non-zero if anything went wrong.
CAPTURE_CMAKE_ERROR <result-var>
Added in version 3.7.
Store in the <result-var> variable -1 if there are any errors
running the command and prevent ctest from returning non-zero if
an error occurs.
OUTPUT_JUNIT <file>
Added in version 3.21.
Write test results to <file> in JUnit XML format. If <file> is a
relative path, it will be placed in the build directory. If
<file> already exists, it will be overwritten. Note that the
resulting JUnit XML file is not uploaded to CDash because it
would be redundant with CTest's Test.xml file.
QUIET Added in version 3.3.
Suppress any CTest-specific non-error messages that would have
otherwise been printed to the console. Output from the
underlying test command is not affected. Summary info detailing
the percentage of passing tests is also unaffected by the QUIET
option.
See also the CTEST_CUSTOM_MAXIMUM_PASSED_TEST_OUTPUT_SIZE <#
variable:CTEST_CUSTOM_MAXIMUM_PASSED_TEST_OUTPUT_SIZE>,
CTEST_CUSTOM_MAXIMUM_FAILED_TEST_OUTPUT_SIZE <#
variable:CTEST_CUSTOM_MAXIMUM_FAILED_TEST_OUTPUT_SIZE> and
CTEST_CUSTOM_TEST_OUTPUT_TRUNCATION <#
variable:CTEST_CUSTOM_TEST_OUTPUT_TRUNCATION> variables, along with
their corresponding ctest(1) <#manual:ctest(1)> command line options
--test-output-size-passed <#cmdoption-ctest-test-output-size-passed>,
--test-output-size-failed <#cmdoption-ctest-test-output-size-failed>,
and --test-output-truncation <#cmdoption-ctest-test-output-truncation>.
Additional Test Measurements
CTest can parse the output of your tests for extra measurements to
report to CDash.
When run as a Dashboard Client <#dashboard-client>, CTest will include
these custom measurements in the Test.xml file that gets uploaded to
CDash.
Check the CDash test measurement documentation <https://github.com/
Kitware/CDash/blob/master/docs/test_measurements.md> for more
information on the types of test measurements that CDash recognizes.
The following example demonstrates how to output a variety of custom
test measurements.
std::cout <<
"<CTestMeasurement type=\"numeric/double\" name=\"score\">28.3</CTestMeasurement>"
<< std::endl;
std::cout <<
"<CTestMeasurement type=\"text/string\" name=\"color\">red</CTestMeasurement>"
<< std::endl;
std::cout <<
"<CTestMeasurement type=\"text/link\" name=\"CMake URL\">https://cmake.org</CTestMeasurement>"
<< std::endl;
std::cout <<
"<CTestMeasurement type=\"text/preformatted\" name=\"Console Output\">" <<
"line 1.\n" <<
" \033[31;1m line 2. Bold red, and indented!\033[0;0ml\n" <<
"line 3. Not bold or indented...\n" <<
"</CTestMeasurement>" << std::endl;
Image Measurements
The following example demonstrates how to upload test images to CDash.
std::cout <<
"<CTestMeasurementFile type=\"image/jpg\" name=\"TestImage\">" <<
"/dir/to/test_img.jpg</CTestMeasurementFile>" << std::endl;
std::cout <<
"<CTestMeasurementFile type=\"image/gif\" name=\"ValidImage\">" <<
"/dir/to/valid_img.gif</CTestMeasurementFile>" << std::endl;
std::cout <<
"<CTestMeasurementFile type=\"image/png\" name=\"AlgoResult\">" <<
"/dir/to/img.png</CTestMeasurementFile>"
<< std::endl;
Images will be displayed together in an interactive comparison mode on
CDash if they are provided with two or more of the following names.
o TestImage
o ValidImage
o BaselineImage
o DifferenceImage2
By convention, TestImage is the image generated by your test, and
ValidImage (or BaselineImage) is basis of comparison used to determine
if the test passed or failed.
If another image name is used it will be displayed by CDash as a static
image separate from the interactive comparison UI.
Attached Files
Added in version 3.21.
The following example demonstrates how to upload non-image files to
CDash.
std::cout <<
"<CTestMeasurementFile type=\"file\" name=\"TestInputData1\">" <<
"/dir/to/data1.csv</CTestMeasurementFile>\n" <<
"<CTestMeasurementFile type=\"file\" name=\"TestInputData2\">" <<
"/dir/to/data2.csv</CTestMeasurementFile>" << std::endl;
If the name of the file to upload is known at configure time, you can
use the ATTACHED_FILES <#prop_test:ATTACHED_FILES> or
ATTACHED_FILES_ON_FAIL <#prop_test:ATTACHED_FILES_ON_FAIL> test
properties instead.
Custom Details
Added in version 3.21.
The following example demonstrates how to specify a custom value for
the Test Details field displayed on CDash.
std::cout <<
"<CTestDetails>My Custom Details Value</CTestDetails>" << std::endl;
Additional Labels
Added in version 3.22.
The following example demonstrates how to add additional labels to a
test at runtime.
std::cout <<
"<CTestLabel>Custom Label 1</CTestLabel>\n" <<
"<CTestLabel>Custom Label 2</CTestLabel>" << std::endl;
Use the LABELS <#prop_test:LABELS> test property instead for labels
that can be determined at configure time.
ctest_update
Perform the CTest Update Step <#ctest-update-step> as a Dashboard
Client <#dashboard-client>.
ctest_update([SOURCE <source-dir>]
[RETURN_VALUE <result-var>]
[CAPTURE_CMAKE_ERROR <result-var>]
[QUIET])
Update the source tree from version control and record results in
Update.xml for submission with the ctest_submit() <#
command:ctest_submit> command.
The options are:
SOURCE <source-dir>
Specify the source directory. If not given, the
CTEST_SOURCE_DIRECTORY <#variable:CTEST_SOURCE_DIRECTORY>
variable is used.
RETURN_VALUE <result-var>
Store in the <result-var> variable the number of files updated
or -1 on error.
CAPTURE_CMAKE_ERROR <result-var>
Added in version 3.13.
Store in the <result-var> variable -1 if there are any errors
running the command and prevent ctest from returning non-zero if
an error occurs.
QUIET Added in version 3.3.
Tell CTest to suppress most non-error messages that it would
have otherwise printed to the console. CTest will still report
the new revision of the repository and any conflicting files
that were found.
The update always follows the version control branch currently checked
out in the source directory. See the CTest Update Step <#ctest-update-
step> documentation for information about variables that change the
behavior of ctest_update().
ctest_upload
Upload files to a dashboard server as a Dashboard Client <#dashboard-
client>.
ctest_upload(FILES <file>... [QUIET] [CAPTURE_CMAKE_ERROR <result-var>])
The options are:
FILES <file>...
Specify a list of files to be sent along with the build results
to the dashboard server.
QUIET Added in version 3.3.
Suppress any CTest-specific non-error output that would have
been printed to the console otherwise.
CAPTURE_CMAKE_ERROR <result-var>
Added in version 3.7.
Store in the <result-var> variable -1 if there are any errors
running the command and prevent ctest from returning non-zero if
an error occurs.
DEPRECATED COMMANDS
These commands are deprecated and are only made available to maintain
backward compatibility. The documentation of each command states the
CMake version in which it was deprecated. Do not use these commands in
new code.
build_name
Disallowed since version 3.0. See CMake Policy CMP0036 <#
policy:CMP0036>.
Use ${CMAKE_SYSTEM} and ${CMAKE_CXX_COMPILER} instead.
build_name(variable)
Sets the specified variable to a string representing the platform and
compiler settings. These values are now available through the
CMAKE_SYSTEM <#variable:CMAKE_SYSTEM> and CMAKE_CXX_COMPILER <#
variable:CMAKE_<LANG>_COMPILER> variables.
exec_program
Changed in version 3.28: This command is available only if policy
CMP0153 <#policy:CMP0153> is not set to NEW. Port projects to the
execute_process() <#command:execute_process> command.
Deprecated since version 3.0: Use the execute_process() <#
command:execute_process> command instead.
Run an executable program during the processing of the CMakeList.txt
file.
exec_program(Executable [directory in which to run]
[ARGS <arguments to executable>]
[OUTPUT_VARIABLE <var>]
[RETURN_VALUE <var>])
The executable is run in the optionally specified directory. The
executable can include arguments if it is double quoted, but it is
better to use the optional ARGS argument to specify arguments to the
program. This is because cmake will then be able to escape spaces in
the executable path. An optional argument OUTPUT_VARIABLE specifies a
variable in which to store the output. To capture the return value of
the execution, provide a RETURN_VALUE. If OUTPUT_VARIABLE is
specified, then no output will go to the stdout/stderr of the console
running cmake.
export_library_dependencies
Disallowed since version 3.0. See CMake Policy CMP0033 <#
policy:CMP0033>.
Use install(EXPORT) <#export> or export() <#command:export> command.
This command generates an old-style library dependencies file.
Projects requiring CMake 2.6 or later should not use the command. Use
instead the install(EXPORT) <#export> command to help export targets
from an installation tree and the export() <#command:export> command to
export targets from a build tree.
The old-style library dependencies file does not take into account
per-configuration names of libraries or the LINK_INTERFACE_LIBRARIES <#
prop_tgt:LINK_INTERFACE_LIBRARIES> target property.
export_library_dependencies(<file> [APPEND])
Create a file named <file> that can be included into a CMake listfile
with the INCLUDE command. The file will contain a number of SET
commands that will set all the variables needed for library dependency
information. This should be the last command in the top level
CMakeLists.txt file of the project. If the APPEND option is specified,
the SET commands will be appended to the given file instead of
replacing it.
install_files
Deprecated since version 3.0: Use the install(FILES) <#files> command
instead.
This command has been superseded by the install() <#command:install>
command. It is provided for compatibility with older CMake code. The
FILES form is directly replaced by the FILES form of the install() <#
command:install> command. The regexp form can be expressed more
clearly using the GLOB form of the file() <#command:file> command.
install_files(<dir> extension file file ...)
Create rules to install the listed files with the given extension into
the given directory. Only files existing in the current source tree or
its corresponding location in the binary tree may be listed. If a file
specified already has an extension, that extension will be removed
first. This is useful for providing lists of source files such as
foo.cxx when you want the corresponding foo.h to be installed. A
typical extension is .h.
install_files(<dir> regexp)
Any files in the current source directory that match the regular
expression will be installed.
install_files(<dir> FILES file file ...)
Any files listed after the FILES keyword will be installed explicitly
from the names given. Full paths are allowed in this form.
The directory <dir> is relative to the installation prefix, which is
stored in the variable CMAKE_INSTALL_PREFIX <#
variable:CMAKE_INSTALL_PREFIX>.
install_programs
Deprecated since version 3.0: Use the install(PROGRAMS) <#programs>
command instead.
This command has been superseded by the install() <#command:install>
command. It is provided for compatibility with older CMake code. The
FILES form is directly replaced by the PROGRAMS form of the install()
<#command:install> command. The regexp form can be expressed more
clearly using the GLOB form of the file() <#command:file> command.
install_programs(<dir> file1 file2 [file3 ...])
install_programs(<dir> FILES file1 [file2 ...])
Create rules to install the listed programs into the given directory.
Use the FILES argument to guarantee that the file list version of the
command will be used even when there is only one argument.
install_programs(<dir> regexp)
In the second form any program in the current source directory that
matches the regular expression will be installed.
This command is intended to install programs that are not built by
cmake, such as shell scripts. See the TARGETS form of the install() <#
command:install> command to create installation rules for targets built
by cmake.
The directory <dir> is relative to the installation prefix, which is
stored in the variable CMAKE_INSTALL_PREFIX <#
variable:CMAKE_INSTALL_PREFIX>.
install_targets
Deprecated since version 3.0: Use the install(TARGETS) <#targets>
command instead.
This command has been superseded by the install() <#command:install>
command. It is provided for compatibility with older CMake code.
install_targets(<dir> [RUNTIME_DIRECTORY dir] target target)
Create rules to install the listed targets into the given directory.
The directory <dir> is relative to the installation prefix, which is
stored in the variable CMAKE_INSTALL_PREFIX <#
variable:CMAKE_INSTALL_PREFIX>. If RUNTIME_DIRECTORY is specified,
then on systems with special runtime files (Windows DLL), the files
will be copied to that directory.
load_command
Disallowed since version 3.0. See CMake Policy CMP0031 <#
policy:CMP0031>.
Load a command into a running CMake.
load_command(COMMAND_NAME <loc1> [loc2 ...])
The given locations are searched for a library whose name is
cmCOMMAND_NAME. If found, it is loaded as a module and the command is
added to the set of available CMake commands. Usually, try_compile()
<#command:try_compile> is used before this command to compile the
module. If the command is successfully loaded a variable named
CMAKE_LOADED_COMMAND_<COMMAND_NAME>
will be set to the full path of the module that was loaded. Otherwise
the variable will not be set.
make_directory
Deprecated since version 3.0: Use the file(MAKE_DIRECTORY) <#make-
directory> command instead.
make_directory(directory)
Creates the specified directory. Full paths should be given. Any
parent directories that do not exist will also be created. Use with
care.
output_required_files
Disallowed since version 3.0. See CMake Policy CMP0032 <#
policy:CMP0032>.
Approximate C preprocessor dependency scanning.
This command exists only because ancient CMake versions provided it.
CMake handles preprocessor dependency scanning automatically using a
more advanced scanner.
output_required_files(srcfile outputfile)
Outputs a list of all the source files that are required by the
specified srcfile. This list is written into outputfile. This is
similar to writing out the dependencies for srcfile except that it
jumps from .h files into .cxx, .c and .cpp files if possible.
qt_wrap_cpp
Deprecated since version 3.14: This command was originally added to
support Qt 3 before the add_custom_command() <#
command:add_custom_command> command was sufficiently mature. The
FindQt4 <#module:FindQt4> module provides the qt4_wrap_cpp() macro,
which should be used instead for Qt 4 projects. For projects using Qt
5 or later, use the equivalent macro provided by Qt itself (e.g. Qt 5
provides qt5_wrap_cpp() <https://doc.qt.io/qt-5/qtcore-cmake-qt5-wrap-
cpp.html>).
Manually create Qt Wrappers.
qt_wrap_cpp(resultingLibraryName DestName SourceLists ...)
Produces moc files for all the .h files listed in the SourceLists. The
moc files will be added to the library using the DestName source list.
Consider updating the project to use the AUTOMOC <#prop_tgt:AUTOMOC>
target property instead for a more automated way of invoking the moc
tool.
qt_wrap_ui
Deprecated since version 3.14: This command was originally added to
support Qt 3 before the add_custom_command() <#
command:add_custom_command> command was sufficiently mature. The
FindQt4 <#module:FindQt4> module provides the qt4_wrap_ui() macro,
which should be used instead for Qt 4 projects. For projects using Qt
5 or later, use the equivalent macro provided by Qt itself (e.g. Qt 5
provides qt5_wrap_ui()).
Manually create Qt user interfaces Wrappers.
qt_wrap_ui(resultingLibraryName HeadersDestName
SourcesDestName SourceLists ...)
Produces .h and .cxx files for all the .ui files listed in the
SourceLists. The .h files will be added to the library using the
HeadersDestNamesource list. The .cxx files will be added to the
library using the SourcesDestNamesource list.
Consider updating the project to use the AUTOUIC <#prop_tgt:AUTOUIC>
target property instead for a more automated way of invoking the uic
tool.
remove
Deprecated since version 3.0: Use the list(REMOVE_ITEM) <#remove-item>
command instead.
remove(VAR VALUE VALUE ...)
Removes VALUE from the variable VAR. This is typically used to remove
entries from a vector (e.g. semicolon separated list). VALUE is
expanded.
subdir_depends
Disallowed since version 3.0. See CMake Policy CMP0029 <#
policy:CMP0029>.
Does nothing.
subdir_depends(subdir dep1 dep2 ...)
Does not do anything. This command used to help projects order
parallel builds correctly. This functionality is now automatic.
subdirs
Deprecated since version 3.0: Use the add_subdirectory() <#
command:add_subdirectory> command instead.
Add a list of subdirectories to the build.
subdirs(dir1 dir2 ...[EXCLUDE_FROM_ALL exclude_dir1 exclude_dir2 ...]
[PREORDER] )
Add a list of subdirectories to the build. The add_subdirectory() <#
command:add_subdirectory> command should be used instead of subdirs
although subdirs will still work. This will cause any CMakeLists.txt
files in the sub directories to be processed by CMake. Any directories
after the PREORDER flag are traversed first by makefile builds, the
PREORDER flag has no effect on IDE projects. Any directories after the
EXCLUDE_FROM_ALL marker will not be included in the top level makefile
or project file. This is useful for having CMake create makefiles or
projects for a set of examples in a project. You would want CMake to
generate makefiles or project files for all the examples at the same
time, but you would not want them to show up in the top level project
or be built each time make is run from the top.
use_mangled_mesa
Disallowed since version 3.0. See CMake Policy CMP0030 <#
policy:CMP0030>.
Copy mesa headers for use in combination with system GL.
use_mangled_mesa(PATH_TO_MESA OUTPUT_DIRECTORY)
The path to mesa includes, should contain gl_mangle.h. The mesa
headers are copied to the specified output directory. This allows
mangled mesa headers to override other GL headers by being added to the
include directory path earlier.
utility_source
Disallowed since version 3.0. See CMake Policy CMP0034 <#
policy:CMP0034>.
Specify the source tree of a third-party utility.
utility_source(cache_entry executable_name
path_to_source [file1 file2 ...])
When a third-party utility's source is included in the distribution,
this command specifies its location and name. The cache entry will not
be set unless the path_to_source and all listed files exist. It is
assumed that the source tree of the utility will have been built before
it is needed.
When cross compiling CMake will print a warning if a utility_source()
command is executed, because in many cases it is used to build an
executable which is executed later on. This doesn't work when cross
compiling, since the executable can run only on their target platform.
So in this case the cache entry has to be adjusted manually so it
points to an executable which is runnable on the build host.
variable_requires
Disallowed since version 3.0. See CMake Policy CMP0035 <#
policy:CMP0035>.
Use the if() <#command:if> command instead.
Assert satisfaction of an option's required variables.
variable_requires(TEST_VARIABLE RESULT_VARIABLE
REQUIRED_VARIABLE1
REQUIRED_VARIABLE2 ...)
The first argument (TEST_VARIABLE) is the name of the variable to be
tested, if that variable is false nothing else is done. If
TEST_VARIABLE is true, then the next argument (RESULT_VARIABLE) is a
variable that is set to true if all the required variables are set.
The rest of the arguments are variables that must be true or not set to
NOTFOUND to avoid an error. If any are not true, an error is reported.
write_file
Deprecated since version 3.0: Use the file(WRITE) <#write> command
instead.
write_file(filename "message to write"... [APPEND])
The first argument is the file name, the rest of the arguments are
messages to write. If the argument APPEND is specified, then the
message will be appended.
NOTE 1: file(WRITE) <#write> and file(APPEND) <#append> do exactly
the same as this one but add some more functionality.
NOTE 2: When using write_file the produced file cannot be used as an
input to CMake (CONFIGURE_FILE, source file ...) because it will lead
to an infinite loop. Use configure_file() <#command:configure_file> if
you want to generate input files to CMake.
Copyright
2000-2024 Kitware, Inc. and Contributors
3.31.11 April 11, 2026 cmake-commands(7)
cmake 3.31.11 - Generated Sun Apr 12 15:32:11 CDT 2026