llvm-config and clang

My CMakeLists.txt depends heavily on llvm-config to provide command-line parameters for compiling my project. However, I’m curious to know whether the output of “llvm-config --cppflags” is intended for consumption by gcc or clang. I’m guessing the answer is “both”, since clang provides support for gcc-compatible command args.

However, I’m wondering whether it would make sense to have an additional --clang argument to llvm-config that would tell it to generate command-line args optimized for clang - omitting arguments that were no-ops, and adding additional clang-specific arguments, assuming that there are any that would be beneficial when compiling programs that link against the LLVM libs.