test cpp RESULT_VARIABLE MEX_RESULT_TRASH OUTPUT_VARIABLE MEX_OUTPUT ERROR_VARIABLE MEX_ERROR_TRASH string(REGEX MATCH"Warning: You are using"MEX_WARNING"${MEX_OUTPUT}") if(MEX_WARNING) string(REGEX REPLACE".*using [a-zA-Z]* version \"([0-9.]*)[^\"]*\".*""\\1"OTHER_COMPILER_VERSION"$