kfunk added a comment.
+1 to apol's recommendation. `... MATCHES "Clang"` is the expression everyone uses. Even in cmake.git: Modules/CMakeDetermineCCompiler.cmake 138: if(CMAKE_C_COMPILER_ID MATCHES "GNU" OR CMAKE_C_COMPILER_ID MATCHES "Clang") Also see: http://stackoverflow.com/questions/10046114/in-cmake-how-can-i-test-if-the-compiler-is-clang REPOSITORY R240 Extra CMake Modules REVISION DETAIL https://phabricator.kde.org/D5089 To: rjvbb, #build_system, #frameworks Cc: kfunk, apol, kde-mac, #frameworks, #build_system