1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 // <iterator> 10 11 // <iterator> 12 // template <class C> constexpr auto empty(const C& c) -> decltype(c.empty()); 13 14 // UNSUPPORTED: c++03, c++11, c++14, c++17 15 16 #include <vector> 17 #include <iterator> 18 19 #include "test_macros.h" 20 21 int main(int, char**) 22 { 23 std::vector<int> c; 24 std::empty(c); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}} 25 26 return 0; 27 } 28