[libcxx-commits] [libcxx] [tzdb] Replace shared_mutex with mutex. (PR #87929)

[Mark de Wever via libcxx-commits]

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

Thanks a lot for this optimization!
Can you add the benchmark results to the commit message, that way it's part of the history and does not depend on the availability of GitHub.

LGTM modulo one nit.

https://github.com/llvm/llvm-project/pull/87929