diff --git a/cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake b/cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake --- a/cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake +++ b/cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake @@ -1,20 +1,28 @@ -include(CheckLinkerFlag OPTIONAL) +include(CMakePushCheckState) -if (COMMAND check_linker_flag) - macro(llvm_check_compiler_linker_flag) - check_linker_flag(${ARGN}) - endmacro() -else() - # Until the minimum CMAKE version is 3.18 +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 builtin compatible, except we assume lang is C or CXX - function(llvm_check_compiler_linker_flag lang flag out_var) - cmake_policy(PUSH) - cmake_policy(SET CMP0056 NEW) - set(_CMAKE_EXE_LINKER_FLAGS_SAVE ${CMAKE_EXE_LINKER_FLAGS}) - set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${flag}") + cmake_push_check_state() + set(CMAKE_REQUIRED_FLAGS "${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") @@ -22,7 +30,6 @@ else() message(FATAL_ERROR "\"${lang}\" is not C or CXX") endif() - set(CMAKE_EXE_LINKER_FLAGS ${_CMAKE_EXE_LINKER_FLAGS_SAVE}) - cmake_policy(POP) - endfunction() -endif() + endif() + cmake_pop_check_state() +endfunction()