volatile and contiguous_iterator do not mix

stl/inc/xutility

@@ -4124,7 +4124,7 @@ _INLINE_VAR constexpr bool _Can_assign_elements<_Source, _Dest, _Memcopy_cat::_M
 // _Memcopy_is_safe<_Iter1, _Iter2> reports whether we can activate the memcopy optimization for arbitrary iterators.
 // It ignores top-level constness on the iterators and on the elements.
 template <class _Iter1, class _Iter2, _Memcopy_cat _Cat>
-_INLINE_VAR constexpr bool _Memcopy_is_safe_helper = _Iterators_are_contiguous<_Iter1, _Iter2> //
+_INLINE_VAR constexpr bool _Memcopy_is_safe_helper = conjunction_v<is_pointer<_Iter1>, is_pointer<_Iter2>> //
     && _Can_assign_elements<remove_reference_t<_Iter_ref_t<_Iter1>>, remove_reference_t<_Iter_ref_t<_Iter2>>, _Cat> //
         && _Can_memcopy_elements<remove_cv_t<remove_reference_t<_Iter_ref_t<_Iter1>>>,
             remove_cv_t<remove_reference_t<_Iter_ref_t<_Iter2>>>, _Cat>;