libcxx/test/std/strings/basic.string/string.capacity/empty.verify.cpp

   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; // constexpr since C++20
  14
  15 // UNSUPPORTED: c++03, c++11, c++14, c++17
  16
  17 #include <string>
  18
  19 void f() {
  20   std::string c;
  21   c.empty(); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
  22 }