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author | Petr Hosek <phosek@google.com> | 2023-02-01 08:25:35 +0000 |
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committer | Petr Hosek <phosek@google.com> | 2023-02-22 04:24:49 +0000 |
commit | efae3174f09560353fb0f3d528bcbffe060d5438 (patch) | |
tree | fe45b3f6a87a91d2f5b61b0fffcc0c536f20a1dc /cmake | |
parent | 0df66569e529be4bcea06f314c02c6af74989704 (diff) | |
download | llvm-efae3174f09560353fb0f3d528bcbffe060d5438.zip llvm-efae3174f09560353fb0f3d528bcbffe060d5438.tar.gz llvm-efae3174f09560353fb0f3d528bcbffe060d5438.tar.bz2 |
[CMake] Unify llvm_check_linker_flag and llvm_check_compiler_linker_flag
These have the same purposes but two different implementations.
llvm_check_compiler_linker_flag uses CMAKE_REQUIRED_FLAGS which affects
flags used both for compilation and linking which is problematic because
some flags may be link-only and trigger unused argument warning when set
during compilation. llvm_check_linker_flag does not have this issue so
we chose it as the prevailaing implementation.
Differential Revision: https://reviews.llvm.org/D143052
Diffstat (limited to 'cmake')
-rw-r--r-- | cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake | 35 | ||||
-rw-r--r-- | cmake/Modules/LLVMCheckLinkerFlag.cmake | 28 |
2 files changed, 28 insertions, 35 deletions
diff --git a/cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake b/cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake deleted file mode 100644 index f61ec05..0000000 --- a/cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake +++ /dev/null @@ -1,35 +0,0 @@ -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() diff --git a/cmake/Modules/LLVMCheckLinkerFlag.cmake b/cmake/Modules/LLVMCheckLinkerFlag.cmake new file mode 100644 index 0000000..e09bbc6 --- /dev/null +++ b/cmake/Modules/LLVMCheckLinkerFlag.cmake @@ -0,0 +1,28 @@ +include(CheckLinkerFlag OPTIONAL) + +if (COMMAND check_linker_flag) + macro(llvm_check_linker_flag) + check_linker_flag(${ARGN}) + endmacro() +else() + # Until the minimum CMAKE version is 3.18 + + include(CheckCXXCompilerFlag) + + # cmake builtin compatible, except we assume lang is C or CXX + function(llvm_check_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} ${flag}") + if("${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() + set(CMAKE_EXE_LINKER_FLAGS ${_CMAKE_EXE_LINKER_FLAGS_SAVE}) + cmake_policy(POP) + endfunction() +endif() |