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 // UNSUPPORTED: c++03, c++11, c++14, c++17
9 
10 // <span>
11 
12 // [[nodiscard]] constexpr bool empty() const noexcept;
13 
14 #include <span>
15 
16 void test() {
17   std::span<int> s1;
18   s1.empty(); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
19 
20   int arr[] = {1, 2, 3};
21   std::span<int, 3> s2{arr};
22   s2.empty(); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
23 }
24