[libcxx-commits] [libcxx] [libc++] Add internal checks for some basic_streambuf invariants (PR #144602)

[A. Jiang via libcxx-commits]

https://github.com/frederick-vs-ja approved this pull request.

Seems like that we should merge this now. CI failures are probably unlated.

https://github.com/llvm/llvm-project/pull/144602