| # Distributed under the OSI-approved BSD 3-Clause License. See accompanying |
| # file Copyright.txt or https://cmake.org/licensing for details. |
| |
| |
| #[=======================================================================[.rst: |
| CheckSourceCompiles |
| ---------------------- |
| |
| .. versionadded:: 3.19 |
| |
| Check if given source compiles and links into an executable. |
| |
| .. command:: check_source_compiles |
| |
| .. code-block:: cmake |
| |
| check_source_compiles(<lang> <code> <resultVar> |
| [FAIL_REGEX <regex1> [<regex2>...]] |
| [SRC_EXT <extension>]) |
| |
| Check that the source supplied in ``<code>`` can be compiled as a source |
| file for the requested language and linked as an executable. The result |
| will be stored in the internal cache variable specified by ``<resultVar>``, |
| with a boolean true value for success and boolean false for failure. If |
| ``FAIL_REGEX`` is provided, then failure is determined by checking if |
| anything in the compiler output matches any of the specified regular |
| expressions. |
| |
| By default, the test source file will be given a file extension that matches |
| the requested language. The ``SRC_EXT`` option can be used to override this |
| with ``.<extension>`` instead. |
| |
| The ``<code>`` must contain a valid main program. For example: |
| |
| .. code-block:: cmake |
| |
| check_source_compiles(C |
| "#include <stdlib.h> |
| #include <stdnoreturn.h> |
| noreturn void f(){ exit(0); } |
| int main(void) { f(); return 1; }" |
| HAVE_NORETURN) |
| |
| check_source_compiles(Fortran |
| "program test |
| error stop |
| end program" |
| HAVE_ERROR_STOP) |
| |
| The underlying check is performed by the :command:`try_compile` command. The |
| compile and link commands can be influenced by setting any of the following |
| variables prior to calling ``check_source_compiles()``: |
| |
| ``CMAKE_REQUIRED_FLAGS`` |
| Additional flags to pass to the compiler. Note that the contents of |
| :variable:`CMAKE_<LANG>_FLAGS <CMAKE_<LANG>_FLAGS>` and its associated |
| configuration-specific variable are automatically added to the compiler |
| command before the contents of ``CMAKE_REQUIRED_FLAGS``. |
| |
| ``CMAKE_REQUIRED_DEFINITIONS`` |
| A :ref:`;-list <CMake Language Lists>` of compiler definitions of the form |
| ``-DFOO`` or ``-DFOO=bar``. A definition for the name specified by |
| ``<resultVar>`` will also be added automatically. |
| |
| ``CMAKE_REQUIRED_INCLUDES`` |
| A :ref:`;-list <CMake Language Lists>` of header search paths to pass to |
| the compiler. These will be the only header search paths used by |
| ``try_compile()``, i.e. the contents of the :prop_dir:`INCLUDE_DIRECTORIES` |
| directory property will be ignored. |
| |
| ``CMAKE_REQUIRED_LINK_OPTIONS`` |
| A :ref:`;-list <CMake Language Lists>` of options to add to the link |
| command (see :command:`try_compile` for further details). |
| |
| ``CMAKE_REQUIRED_LIBRARIES`` |
| A :ref:`;-list <CMake Language Lists>` of libraries to add to the link |
| command. These can be the name of system libraries or they can be |
| :ref:`Imported Targets <Imported Targets>` (see :command:`try_compile` for |
| further details). |
| |
| ``CMAKE_REQUIRED_QUIET`` |
| If this variable evaluates to a boolean true value, all status messages |
| associated with the check will be suppressed. |
| |
| The check is only performed once, with the result cached in the variable |
| named by ``<resultVar>``. Every subsequent CMake run will re-use this cached |
| value rather than performing the check again, even if the ``<code>`` changes. |
| In order to force the check to be re-evaluated, the variable named by |
| ``<resultVar>`` must be manually removed from the cache. |
| |
| #]=======================================================================] |
| |
| include_guard(GLOBAL) |
| include(Internal/CheckSourceCompiles) |
| |
| function(CHECK_SOURCE_COMPILES _lang _source _var) |
| cmake_check_source_compiles(${_lang} "${_source}" ${_var} ${ARGN}) |
| endfunction() |