[llvm-branch-commits] [clang] [Serialization] Code cleanups and polish 83233 (PR #83237)

[Ilya Biryukov via llvm-branch-commits]

ilya-biryukov wrote:

After endless hours and recompilations, I finally have this to share.
It could probably be smaller, but I decided to share this as soon as it crashed outside of our monorepo. 

[module.tgz](https://github.com/llvm/llvm-project/files/15223606/module.tgz)
^^ If you run build.sh with Clang 16, it builds. However, it fails with the current patch. 
See out/errors for a list of errors I get on my machine. 
This breaks with libstdc++ 13, but also latest libc++ (which is what we use in our monorepo).

https://github.com/llvm/llvm-project/pull/83237