https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102358
--- Comment #6 from Artur Bać <gcc at ebasoft dot com.pl> --- My bad. copy itself is constexpr since c++20, I was misleaded by overload used for move_iterator with copy that has missing constexpr template<typename _Iterator> auto __miter_base(move_iterator<_Iterator> __it)
