[libc-commits] [clang] [libc] [libcxx] [libc][libcxx] Support for building libc++ against LLVM libc (PR #99287)

[Joseph Huber via libc-commits]

https://github.com/jhuber6 approved this pull request.

I tested this locally and it worked quite well thanks.

My nit is that we should add a check that mirrors the already existing `LIBCXXABI_USE_LLVM_UNWINDER` flag, which prints an error if `libunwind` isn't in the runtimes list. After that LG from the `libc` side, but I'd wait for a word from the `libcxx` side.

https://github.com/llvm/llvm-project/pull/99287