Sharpie/homebrew — comment on commit d17b44da33c9f83ff2b4691de3652157172dcf67
File: Library/Homebrew/formula.rb line 344
By Sharpie:

Yeah, string comparisons are safe. We do the same thing with `MACOSX_VERSION`.

However, Max noted that `xcode_version` shouldn't be used---probably due to issues with alternate installers such as the osx-gcc-installer. A better way to do this check might be:

```ruby
if MacOS.has_gcc?
# recommend GCC
else
# recommend Clang
end
```

But as far as I know, we don't have something like `MacOS.has_gcc?`.