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 // <string> 10 11 // class deque 12 13 // bool empty() const noexcept; 14 15 // UNSUPPORTED: c++03, c++11, c++14, c++17 16 17 #include <string> 18 19 #include "test_macros.h" 20 21 bool test() { 22 std::string c; 23 c.empty(); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}} 24 25 return true; 26 } 27 28 int main(int, char**) 29 { 30 test(); 31 #if TEST_STD_VER > 17 32 // static_assert(test()); 33 #endif 34 35 return 0; 36 } 37