libcxx/test/std/containers/container.adaptors/flat.map/flat.map.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 // UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
  10
  11 // <flat_map>
  12
  13 // [[nodiscard]] bool empty() const noexcept;
  14
  15 #include <flat_map>
  16
  17 void f() {
  18   std::flat_map<int, int> c;
  19   c.empty(); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
  20 }