[llvm-branch-commits] [libcxx] [lldb] release/21.x: [libc++] Ensure that we restore invariants in basic_filebuf::overflow (#147389) (PR #155712)

[Tulio Magno Quites Machado Filho via llvm-branch-commits]

tuliom wrote:

Results are much better now.
The AIX failures are unrelated to this PR.
cmake is failing to generate the ABI list file:
```
ABI list file not generated for configuration powerpc64-ibm-aix7.2.0.0.libcxxabi.v1.stable.exceptions.nonew, `check-cxx-abilist` will not be available.
```

https://github.com/llvm/llvm-project/pull/155712