[libc-commits] [libc] [libc] Revert #73704 and subsequent fixes #73984, #74026 (PR #74355)

[Nick Desaulniers via libc-commits]

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

That's ok, I look forward to getting this relanded (with the proper infrastructure in place landed first). Please use distinct PRs for each added entrypoint.

https://github.com/llvm/llvm-project/pull/74355