1 // -*- C++ -*-
2 //===----------------------------------------------------------------------===//
3 //
4 // The LLVM Compiler Infrastructure
5 //
6 // This file is dual licensed under the MIT and the University of Illinois Open
7 // Source Licenses. See LICENSE.TXT for details.
8 //
9 //===----------------------------------------------------------------------===//
10
11 // <regex>
12
13 // class match_results<BidirectionalIterator, Allocator>
14 // bool empty() const;
15
16 // UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
17 // UNSUPPORTED: clang-3.3, clang-3.4, clang-3.5, clang-3.6, clang-3.7, clang-3.8
18
19 #include <regex>
20
21 #include "test_macros.h"
22
main()23 int main ()
24 {
25 std::match_results<const char*> c;
26 c.empty(); // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
27 }
28