diff --git a/Core/CppMicroServices/CMake/usFunctionCheckCompilerFlags.cmake b/Core/CppMicroServices/CMake/usFunctionCheckCompilerFlags.cmake index d9917e4a5e..5aef7e2ccd 100644 --- a/Core/CppMicroServices/CMake/usFunctionCheckCompilerFlags.cmake +++ b/Core/CppMicroServices/CMake/usFunctionCheckCompilerFlags.cmake @@ -1,64 +1,64 @@ # # Helper macro allowing to check if the given flags are supported # by the underlying build tool # # If the flag(s) is/are supported, they will be appended to the string identified by RESULT_VAR # # Usage: # usFunctionCheckCompilerFlags(FLAGS_TO_CHECK VALID_FLAGS_VAR) # # Example: # # set(myflags) # usFunctionCheckCompilerFlags("-fprofile-arcs" myflags) # message(1-myflags:${myflags}) # usFunctionCheckCompilerFlags("-fauto-bugfix" myflags) # message(2-myflags:${myflags}) # usFunctionCheckCompilerFlags("-Wall" myflags) # message(1-myflags:${myflags}) # # The output will be: # 1-myflags: -fprofile-arcs # 2-myflags: -fprofile-arcs # 3-myflags: -fprofile-arcs -Wall -include(TestCXXAcceptsFlag) +include(CheckCXXCompilerFlag) function(usFunctionCheckCompilerFlags FLAG_TO_TEST RESULT_VAR) if(FLAG_TO_TEST STREQUAL "") message(FATAL_ERROR "FLAG_TO_TEST shouldn't be empty") endif() # Clear all flags. If not, existing flags triggering warnings might lead to # false-negatives when checking for certain compiler flags. set(CMAKE_C_FLAGS ) set(CMAKE_C_FLAGS_DEBUG ) set(CMAKE_C_FLAGS_MINSIZEREL ) set(CMAKE_C_FLAGS_RELEASE ) set(CMAKE_C_FLAGS_RELWITHDEBINFO ) set(CMAKE_CXX_FLAGS ) set(CMAKE_CXX_FLAGS_DEBUG ) set(CMAKE_CXX_FLAGS_MINSIZEREL ) set(CMAKE_CXX_FLAGS_RELEASE ) set(CMAKE_CXX_FLAGS_RELWITHDEBINFO ) # Internally, the macro CMAKE_CXX_COMPILER_FLAG calls TRY_COMPILE. To avoid # the cost of compiling the test each time the project is configured, the variable set by # the macro is added to the cache so that following invocation of the macro with # the same variable name skip the compilation step. # For that same reason, the usFunctionCheckCompilerFlags function appends a unique suffix to # the HAS_CXX_FLAG variable. This suffix is created using a 'clean version' of the # flag to test. The value of HAS_CXX_FLAG_${suffix} additonally needs to be a valid # pre-processor token because CHECK_CXX_COMPILER_FLAG adds it as a definition to the compiler # arguments. An invalid token triggers compiler warnings, which in case of the "-Werror" flag # leads to false-negative checks. string(REGEX REPLACE "[/-]" "_" suffix ${FLAG_TO_TEST}) string(REGEX REPLACE "[, \\$\\+\\*\\{\\}\\(\\)\\#]" "" suffix ${suffix}) CHECK_CXX_COMPILER_FLAG(${FLAG_TO_TEST} HAS_CXX_FLAG_${suffix}) if(HAS_CXX_FLAG_${suffix}) set(${RESULT_VAR} "${${RESULT_VAR}} ${FLAG_TO_TEST}" PARENT_SCOPE) endif() endfunction()