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# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.
#[=======================================================================[.rst:
CheckCCompilerFlag
------------------
Check whether the C compiler supports a given flag.
.. command:: check_c_compiler_flag
.. code-block:: cmake
check_c_compiler_flag(<flag> <var>)
Check that the ``<flag>`` is accepted by the compiler without
a diagnostic. Stores the result in an internal cache entry
named ``<var>``.
This command temporarily sets the ``CMAKE_REQUIRED_DEFINITIONS`` variable
and calls the ``check_c_source_compiles`` macro from the
:module:`CheckCSourceCompiles` module. See documentation of that
module for a listing of variables that can otherwise modify the build.
A positive result from this check indicates only that the compiler did not
issue a diagnostic message when given the flag. Whether the flag has any
effect or even a specific one is beyond the scope of this module.
.. note::
Since the :command:`try_compile` command forwards flags from variables
like :variable:`CMAKE_C_FLAGS <CMAKE_<LANG>_FLAGS>`, unknown flags
in such variables may cause a false negative for this check.
#]=======================================================================]
include_guard(GLOBAL)
include(CheckCSourceCompiles)
include(CheckCompilerFlag)
macro (CHECK_C_COMPILER_FLAG _FLAG _RESULT)
check_compiler_flag(C "${_FLAG}" ${_RESULT})
endmacro ()
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