https://en.cppreference.com/w/cpp/memory/polymorphic_allocator/destroy
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/n4713.pdf §23.12.3.2 #14
Seems to be missing.
https://github.com/microsoft/STL/blob/master/stl/inc/xpolymorphic_allocator.h#L190
https://godbolt.org/z/iFfpPT

I had expected something like:

    template<class _Ty>
    void destroy(_Ty* _Ptr) {
        // destroys _Ptr as if by _Ptr->~_Ty().
        _Ptr->~_Ty();
    }

If this is indeed so, I can provide a PR.

Also tracked by DevCom-394908 and Microsoft-internal VSO-737704 / AB#737704.