if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
string(REGEX MATCHALL "-std=[^ ]+" cxx_std_found ${CMAKE_CXX_FLAGS} " dummy@rg")
if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
string(REGEX MATCHALL "-std=[^ ]+" cxx_std_found ${CMAKE_CXX_FLAGS} " dummy@rg")