[libcxx-commits] [libcxx] [libc++][NFC] Mark P1869R1 as implemented (PR #107746)

[Louis Dionne via libcxx-commits]

https://github.com/ldionne approved this pull request.

LGTM, let's just wait for https://github.com/llvm/llvm-project/pull/107900 to land.

https://github.com/llvm/llvm-project/pull/107746