Hello. It's unrelated, but since I was just touching on something similar, I'll write a little something.
In the case of clang, we can display which directory is targeted with a command like the following. clang -E -x c -Wp,-v /dev/null /usr/src/contrib/llvm-project/clang/lib/Driver/ToolChains/FreeBSD.cpp is causing those FreeBSD-specific values to be inserted. If there was something you were concerned about in that mechanism, please feel free to use these as shortcuts :) Regards.
