25fe428ed2
If you have Homebrew LLVM installed, `brew config` will show
Clang: 12.0.1 build (parse error)
because Homebrew LLVM does not give a build number. Some installations
from the system package manager do have this information, so let's show
it if it's available but skip complaining if not.
I've kept the original code for macOS because we always expect Apple's
build number to show there.
Library
This directory contains all the code run by the official brew command in Homebrew and all formulae (package descriptions) in taps (repositories containing formulae) in Taps subdirectories.