libcxx/test/std/containers/sequences/array/empty.verify.cpp

   1 // -*- C++ -*-
   2 //===----------------------------------------------------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 // <array>
  11
  12 // class array
  13
  14 // bool empty() const noexcept;
  15
  16 // UNSUPPORTED: c++03, c++11, c++14, c++17
  17
  18 #include <array>
  19
  20 #include "test_macros.h"
  21
  22 int main(int, char**)
  23 {
  24
  25     std::array<int, 1> c;
  26     c.empty(); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
  27     std::array<int, 0> c0;
  28     c0.empty(); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
  29
  30     return 0;
  31 }