C++程序  |  29行  |  748 B

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

// <set>

// class set

// bool empty() const noexcept;

// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
// UNSUPPORTED: clang-3.3, clang-3.4, clang-3.5, clang-3.6, clang-3.7, clang-3.8

#include <set>

#include "test_macros.h"

int main ()
{
    std::set<int> c;
    c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
}