[clang] [compiler-rt] [libcxx] [libunwind] [llvm] [openmp] [cmake] switch to CMake's native `check_{compiler,linker}_flag` (PR #96171)

[via llvm-commits]

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@@ -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()
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h-vetinari wrote:

see here...

https://github.com/llvm/llvm-project/pull/96171