[clang] [libcxx] [Clang][WIP] Normalize constraints before checking for satisfaction (PR #141776)

[Younan Zhang via cfe-commits]

https://github.com/zyn0217 commented:

Thank you very much for putting it up and the incredible work!

I left some notes, mostly are those that I didn't get around to yet (and I think they should be useful); so maybe we want to resolve them before we move forward.

Also let's not forget the release note :)

https://github.com/llvm/llvm-project/pull/141776