[libcxx-commits] [compiler-rt] [libcxx] [libcxxabi] [libunwind] [runtimes][PAC] Harden unwinding when possible (PR #143230)

[Daniil Kovalev via libcxx-commits]

kovdan01 wrote:

@ojhunt Thanks for an update! I've resolved several threads, but some things should still be fixed.

Please let me know if you have any comments/questions or any help is needed from my side.

### Trivial style-related issues

These require almost zero effort to apply. Please consider fixing these first so we do not need to worry about them anymore.

1. https://github.com/llvm/llvm-project/pull/143230#discussion_r2388284017
2. https://github.com/llvm/llvm-project/pull/143230#discussion_r2388324262
3. https://github.com/llvm/llvm-project/pull/143230#discussion_r2388325718

### Non-trivial styling-related issues

Refactor preprocessor checks against ptrauth. See thread https://github.com/llvm/llvm-project/pull/143230#discussion_r2369029642 and proposed fix 644405b56cfa59dd3787119182df087dff6e756c

### Breaking change to be reverted

> > ### An issue causing a runtime crash
> > Do not mix pac-ret and ptrauth_returns. See thread https://github.com/llvm/llvm-project/pull/143230/files#r2369419226 and commit [ced8b99](https://github.com/llvm/llvm-project/commit/ced8b99373c9b0756f1718999996f44a74bdf46d).
> 
> Fixed with an arm64e guard.

This does not seem to fix the originally described issue, moreover, it looks like this breaks previously working behavior. See https://github.com/llvm/llvm-project/pull/143230#discussion_r2388356981.

https://github.com/llvm/llvm-project/pull/143230