[libcxx-commits] [libcxx] [libcxx] Allow string to use SSO in constant evaluation. (PR #66576)

[via libcxx-commits]

https://github.com/philnik777 requested changes to this pull request.

I think this looks quite good. I'd like a libc++-specific test for something simple like `constinit std::string my_str = "";` and a short paragraph in `libcxx/docs/UsingLibcxx.rst` about this. Maybe something at the bottom about unspecified behaviour which we define.

https://github.com/llvm/llvm-project/pull/66576