Improve the CMake C++ flag checker
This checks the flag on the compiler AND linker which allows it to work
with flags such as -flto and -fsanitize=address
diff --git a/cmake/AddCXXCompilerFlag.cmake b/cmake/AddCXXCompilerFlag.cmake
index 7c0f5a3..870f11a 100644
--- a/cmake/AddCXXCompilerFlag.cmake
+++ b/cmake/AddCXXCompilerFlag.cmake
@@ -20,18 +20,17 @@
include(CheckCXXCompilerFlag)
function(add_cxx_compiler_flag FLAG)
- if(ARGV1)
- set(VARIANT ${ARGV1})
- string(TOLOWER ${VARIANT} VARIANT)
- set(VARIANT " ${VARIANT}")
- endif()
- string(TOUPPER "HAVE_${FLAG}" SANITIZED_FLAG)
+ string(TOUPPER "HAVE_CXX_FLAG_${FLAG}" SANITIZED_FLAG)
+ string(REPLACE "+" "X" SANITIZED_FLAG ${SANITIZED_FLAG})
string(REGEX REPLACE "[^A-Za-z_0-9]" "_" SANITIZED_FLAG ${SANITIZED_FLAG})
string(REGEX REPLACE "_+" "_" SANITIZED_FLAG ${SANITIZED_FLAG})
- check_cxx_compiler_flag(${FLAG} ${SANITIZED_FLAG})
+ set(CMAKE_REQUIRED_FLAGS "${FLAG}")
+ check_cxx_compiler_flag("" ${SANITIZED_FLAG})
if(${SANITIZED_FLAG})
- string(REGEX REPLACE "[^A-Za-z_0-9]" "_" VARIANT "${VARIANT}")
- string(TOUPPER "${VARIANT}" VARIANT)
+ set(VARIANT ${ARGV1})
+ if(ARGV1)
+ string(TOUPPER "_${VARIANT}" VARIANT)
+ endif()
set(CMAKE_CXX_FLAGS${VARIANT} "${CMAKE_CXX_FLAGS${VARIANT}} ${FLAG}" PARENT_SCOPE)
endif()
endfunction()
