If you’re asking whether the default compiler toolchain XCode comes with OpenMP support, then the answer is “no”. Apple doesn’t seem to believe in OpenMP. If you’re asking whether there exist compilers for macOS supporting OpenMP, then the answer is “any other compiler than the default one will likely work”. As you found out, most people tend to install vanilla clang with openmp with homebrew. I believe just installing the llvm openmp package with homebrew, without the full compiler toolchain, should be sufficient for building openmp code with apple clang, but you may need to somehow inform the compiler where to find the openmp runtime.