xref: /llvm-project/cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake (revision 89946bda5e1c7ceaf6d26634cc8c8c9498d9f7be)
1include(CMakePushCheckState)
2include(CheckCompilerFlag)
3
4function(llvm_check_compiler_linker_flag lang flag out_var)
5  # If testing a flag with check_compiler_flag, it gets added to the compile
6  # command only, but not to the linker command in that test. If the flag
7  # is vital for linking to succeed, the test would fail even if it would
8  # have succeeded if it was included on both commands.
9  #
10  # Therefore, try adding the flag to CMAKE_REQUIRED_FLAGS, which gets
11  # added to both compiling and linking commands in the tests.
12
13  cmake_push_check_state()
14  set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} ${flag}")
15  check_compiler_flag("${lang}" "" ${out_var})
16  cmake_pop_check_state()
17endfunction()
18