During development, I have been using the attached patch to simulate
libc collation versions on macOS. It just uses the internal major OS
version number. I don't know to what the extend the libc locales on
macOS are maintained or updated at all, so I don't know what practical
effect this would have. Again, it's mainly for development. If there
is interest from others, I think we could add this, maybe disabled by
default, or we just keep it in the mailing list archives for interested
parties.
