[libcxx-commits] [libcxx] [libcxx] Implementation of P1831R1 (PR #101439)

[Christopher Di Bella via libcxx-commits]

https://github.com/cjdb requested changes to this pull request.

I'll give a proper review later on, but for now:

* Please update the commit subject so that it describes what the change is.
* Please add `Closes #100038` to your commit message on a separate line so that #100038 is automatically closed when this PR lands.

https://github.com/llvm/llvm-project/pull/101439