| include(CMakePushCheckState) |
| |
| include(CheckCompilerFlag OPTIONAL) |
| |
| if(NOT COMMAND check_compiler_flag) |
| include(CheckCCompilerFlag) |
| include(CheckCXXCompilerFlag) |
| endif() |
| |
| function(llvm_check_compiler_linker_flag lang flag out_var) |
| # If testing a flag with check_c_compiler_flag, it gets added to the compile |
| # command only, but not to the linker command in that test. If the flag |
| # is vital for linking to succeed, the test would fail even if it would |
| # have succeeded if it was included on both commands. |
| # |
| # Therefore, try adding the flag to CMAKE_REQUIRED_FLAGS, which gets |
| # added to both compiling and linking commands in the tests. |
| |
| cmake_push_check_state() |
| set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} ${flag}") |
| if(COMMAND check_compiler_flag) |
| check_compiler_flag("${lang}" "" ${out_var}) |
| else() |
| # Until the minimum CMAKE version is 3.19 |
| # cmake builtin compatible, except we assume lang is C or CXX |
| if("${lang}" STREQUAL "C") |
| check_c_compiler_flag("" ${out_var}) |
| elseif("${lang}" STREQUAL "CXX") |
| check_cxx_compiler_flag("" ${out_var}) |
| else() |
| message(FATAL_ERROR "\"${lang}\" is not C or CXX") |
| endif() |
| endif() |
| cmake_pop_check_state() |
| endfunction() |