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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:
CheckLinkerFlag
---------------
.. versionadded:: 3.18
Check whether the compiler supports a given link flag.
.. command:: check_linker_flag
.. code-block:: cmake
check_linker_flag(<lang> <flag> <var>)
Check that the link ``<flag>`` is accepted by the ``<lang>`` compiler without
a diagnostic. Stores the result in an internal cache entry named ``<var>``.
This command temporarily sets the ``CMAKE_REQUIRED_LINK_OPTIONS`` variable
and calls the :command:`check_source_compiles` command from the
:module:`CheckSourceCompiles` module. See that module's documentation
for a listing of variables that can otherwise modify the build.
The underlying implementation relies on the :prop_tgt:`LINK_OPTIONS` property
to check the specified flag. The ``LINKER:`` prefix, as described in the
:command:`target_link_options` command, can be used as well.
A positive result from this check indicates only that the compiler did not
issue a diagnostic message when given the link 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_<LANG>_FLAGS`, unknown flags in such variables may
cause a false negative for this check.
#]=======================================================================]
include_guard(GLOBAL)
include(Internal/CheckLinkerFlag)
function(CHECK_LINKER_FLAG _lang _flag _var)
cmake_check_linker_flag(${_lang} "${_flag}" ${_var})
endfunction()
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