Thinking about this more, clang-cl is also packaged in LLVM/clang in most distros, and as such doesn't have the ".exe" extension. For instance, ArchLinux clang's package installs /usr/bin/clang-cl. https://archlinux.org/packages/extra/x86_64/clang/ Not sure if it should be searched before or after clang-cl.exe.
-- Antonin
