
Replace `&__rhs` with `_VSTD::addressof(__rhs)` to guard against ADL hijacking of `operator&` in `operator=`. Thanks to @CaseyCarter for bringing it to our attention. Similar issues with hijacking `operator&` still exist, they will be addressed separately. Reviewed By: #libc, Quuxplusone, ldionne Differential Revision: https://reviews.llvm.org/D110852