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
10
11 // Test the libc++ extension that std::views::transform is marked as [[nodiscard]].
12
13 #include <ranges>
14
test()15 void test() {
16 int range[] = {1, 2, 3};
17 auto f = [](int i) { return i; };
18
19 std::views::transform(f); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
20 std::views::transform(range, f); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
21 range | std::views::transform(f); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
22 std::views::all | std::views::transform(f); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
23 }
24