Using pkg-config to find `libomp` on mac m1.

[Sam James]

Pradyot Ranjan <rickprimeranjan at gmail.com> writes:

> On macOS, I have to use compiler options to find libomp, can they be removed and we can use pkg-config from Homebrew that
> should be able to do it automatically? The reason for this is because Apple Clang does not come with the OpenMP
> specification – however, other compilers such as LLVM and GCC do.
>
> I tried doing `pkg-config --exists --print-errors libomp` but it throws errors:
>

Unfortunately, LLVM does not distribute pkg-config (.pc) files. We wish
they would.