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 | // std::sort |
10 | |
11 | #include <algorithm> |
12 | #include <iterator> |
13 | #include <type_traits> |
14 | #include <utility> |
15 | |
16 | struct BadIter { |
17 | struct Value { |
18 | friend bool operator==(const Value& x, const Value& y); |
19 | friend bool operator!=(const Value& x, const Value& y); |
20 | friend bool operator< (const Value& x, const Value& y); |
21 | friend bool operator<=(const Value& x, const Value& y); |
22 | friend bool operator> (const Value& x, const Value& y); |
23 | friend bool operator>=(const Value& x, const Value& y); |
24 | friend void swap(Value, Value); |
25 | }; |
26 | |
27 | using iterator_category = std::random_access_iterator_tag; |
28 | using value_type = Value; |
29 | using reference = Value&; |
30 | using difference_type = long; |
31 | using pointer = Value*; |
32 | |
33 | Value operator*() const; // Not `Value&`. |
34 | reference operator[](difference_type n) const; |
35 | |
36 | BadIter& operator++(); |
37 | BadIter& operator--(); |
38 | BadIter operator++(int); |
39 | BadIter operator--(int); |
40 | |
41 | BadIter& operator+=(difference_type n); |
42 | BadIter& operator-=(difference_type n); |
43 | friend BadIter operator+(BadIter x, difference_type n); |
44 | friend BadIter operator+(difference_type n, BadIter x); |
45 | friend BadIter operator-(BadIter x, difference_type n); |
46 | friend difference_type operator-(BadIter x, BadIter y); |
47 | |
48 | friend bool operator==(const BadIter& x, const BadIter& y); |
49 | friend bool operator!=(const BadIter& x, const BadIter& y); |
50 | friend bool operator< (const BadIter& x, const BadIter& y); |
51 | friend bool operator<=(const BadIter& x, const BadIter& y); |
52 | friend bool operator> (const BadIter& x, const BadIter& y); |
53 | friend bool operator>=(const BadIter& x, const BadIter& y); |
54 | }; |
55 | |
56 | // Verify that iterators with incorrect `iterator_traits` are rejected. This protects against potential undefined |
57 | // behavior when these iterators are passed to standard algorithms. |
58 | void test() { |
59 | std::sort(first: BadIter(), last: BadIter()); |
60 | //expected-error-re@*:* {{static assertion failed {{.*}}It looks like your iterator's `iterator_traits<It>::reference` does not match the return type of dereferencing the iterator}} |
61 | } |
62 | |