diff options
| -rw-r--r-- | cmake/modules/HandleLLVMOptions.cmake | 22 |
1 files changed, 12 insertions, 10 deletions
diff --git a/cmake/modules/HandleLLVMOptions.cmake b/cmake/modules/HandleLLVMOptions.cmake index 8e4b6bbdaf..b40103ca18 100644 --- a/cmake/modules/HandleLLVMOptions.cmake +++ b/cmake/modules/HandleLLVMOptions.cmake @@ -335,23 +335,25 @@ if (UNIX AND append("-fcolor-diagnostics" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) endif() -# Clang prior to 3.5 ignored -fno-function-sections. -# It's pretty hard to test directly, so we rely on the version number. -if( ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang") AND (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.5) ) - set(LLVM_COMPILER_HAS_BROKEN_FNO_FUNCTION_SECTIONS ON) -endif() - # Add flags for add_dead_strip(). # FIXME: With MSVS, consider compiling with /Gy and linking with /OPT:REF? # But MinSizeRel seems to add that automatically, so maybe disable these # flags instead if LLVM_NO_DEAD_STRIP is set. if(NOT CYGWIN AND NOT WIN32) if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin") - # Don't add -ffunction-section if it can be disabled with -fno-function-sections. - # Doing so will break sanitizers. - if (NOT LLVM_COMPILER_HAS_BROKEN_FNO_FUNCTION_SECTIONS) - append("-ffunction-sections -fdata-sections" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) + check_c_compiler_flag("-Werror -fno-function-sections" C_SUPPORTS_FNO_FUNCTION_SECTIONS) + if (C_SUPPORTS_FNO_FUNCTION_SECTIONS) + # Don't add -ffunction-section if it can be disabled with -fno-function-sections. + # Doing so will break sanitizers. + check_c_compiler_flag("-Werror -ffunction-sections" C_SUPPORTS_FFUNCTION_SECTIONS) + check_cxx_compiler_flag("-Werror -ffunction-sections" CXX_SUPPORTS_FFUNCTION_SECTIONS) + append_if(C_SUPPORTS_FFUNCTION_SECTIONS "-ffunction-sections" CMAKE_C_FLAGS) + append_if(CXX_SUPPORTS_FFUNCTION_SECTIONS "-ffunction-sections" CMAKE_CXX_FLAGS) endif() + check_c_compiler_flag("-Werror -fdata-sections" C_SUPPORTS_FDATA_SECTIONS) + check_cxx_compiler_flag("-Werror -fdata-sections" CXX_SUPPORTS_FDATA_SECTIONS) + append_if(C_SUPPORTS_FDATA_SECTIONS "-fdata-sections" CMAKE_C_FLAGS) + append_if(CXX_SUPPORTS_FDATA_SECTIONS "-fdata-sections" CMAKE_CXX_FLAGS) endif() endif() |