[libcxx-commits] [libcxx] [libcxx] Define _LIBCPP_HAS_C8RTOMB_MBRTOC8 for picolibc (PR #152724)

[Victor Campos via libcxx-commits]

vhscampos wrote:

@philnik777 I've changed it around to unconditionally define the macro for clang, and then xfail tests in platforms whose C library doesn't provide support.

The CI premerge failures AFAIK are unrelated to the patch.

https://github.com/llvm/llvm-project/pull/152724