[libcxx-commits] [libcxx] [libc++] Implement `std::function_ref` (PR #186692)

[via libcxx-commits]

https://github.com/Kim-J-Smith commented:

Missing cv-qualifier constraint in *is-convertible-from-specialization* according to [func.wrap.ref.ctor]/2.

https://github.com/llvm/llvm-project/pull/186692