1 // PR c++/67161 2 // { dg-do compile { target c++14 } } 3 // { dg-additional-options "-Wno-return-type" } 4 5 template <typename _Tp> struct integral_constant { 6 static constexpr _Tp value = 0; 7 }; 8 template <bool, typename, typename> struct conditional; 9 template <typename...> struct __or_; 10 template <typename _B1, typename _B2> 11 struct __or_<_B1, _B2> : conditional<1, _B1, _B2>::type {}; 12 template <typename...> struct __and_; 13 template <typename> struct __not_ : integral_constant<bool> {}; 14 template <typename> struct __is_void_helper : integral_constant<bool> {}; 15 template <typename> struct is_void : __is_void_helper<int> {}; 16 template <bool, typename _Iftrue, typename> struct conditional { 17 typedef _Iftrue type; 18 }; 19 template <bool _Cond, typename _Iftrue, typename _Iffalse> 20 using conditional_t = typename conditional<_Cond, _Iftrue, _Iffalse>::type; 21 template <typename...> using common_type_t = int; 22 template <typename, int> struct array {}; 23 template <typename _Tp> constexpr int is_void_v = is_void<_Tp>::value; 24 template <typename _Dest = void, typename... _Types> 25 constexpr auto make_array() 26 -> array<conditional_t<is_void_v<_Dest>, common_type_t<>, _Dest>, 27 sizeof...(_Types)> { 28 static_assert(__or_<__not_<is_void<_Dest>>, __and_<>>::value, ""); // { dg-error "static assert" } 29 } 30 auto d = make_array(); 31