// -*- C++ -*- //===----------------------------------------------------------------------===// // // The LLVM Compiler Infrastructure // // This file is dual licensed under the MIT and the University of Illinois Open // Source Licenses. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // UNSUPPORTED: c++98, c++03, c++11, c++14 // <variant> // template <size_t I, class T> struct variant_alternative; // undefined // template <size_t I, class T> struct variant_alternative<I, const T>; // template <size_t I, class T> struct variant_alternative<I, volatile T>; // template <size_t I, class T> struct variant_alternative<I, const volatile T>; // template <size_t I, class T> // using variant_alternative_t = typename variant_alternative<I, T>::type; // // template <size_t I, class... Types> // struct variant_alternative<I, variant<Types...>>; #include <memory> #include <type_traits> #include <variant> int main() { using V = std::variant<int, void *, const void *, long double>; std::variant_alternative<4, V>::type foo; // expected-error@variant:* {{Index out of bounds in std::variant_alternative<>}} }