#ifndef _LIBCPP_ALGORITHM #define _LIBCPP_ALGORITHM template <class _Tp, _Tp> struct integral_constant { static const _Tp value = _Tp(); }; template <class _Tp> struct is_nothrow_default_constructible : integral_constant<bool, __is_constructible(_Tp)> {}; template <class _Tp> struct is_nothrow_move_constructible : integral_constant<bool, __is_constructible(_Tp, _Tp)> {}; class allocator {}; #endif