cmake COMPILER_RT_HAS_UNINITIALIZED_FLAG examples

Lewuathe/mlir-hello thirdparty/llvm-project/compiler-rt/cmake/config-ix.cmake :166

check_cxx_compiler_flag("-Werror -Wuninitialized" COMPILER_RT_HAS_UNINITIALIZED_FLAG)

CTSRD-CHERI/cheribsd contrib/subrepo-cheri-compiler-rt/cmake/config-ix.cmake :143

check_cxx_compiler_flag(-Werror -Wuninitialized COMPILER_RT_HAS_UNINITIALIZED_FLAG)