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 |
10 | |
11 | // <vector> |
12 | |
13 | // void swap(vector& c) |
14 | // noexcept(!allocator_type::propagate_on_container_swap::value || |
15 | // __is_nothrow_swappable<allocator_type>::value); |
16 | // |
17 | // In C++17, the standard says that swap shall have: |
18 | // noexcept(allocator_traits<Allocator>::propagate_on_container_swap::value || |
19 | // allocator_traits<Allocator>::is_always_equal::value); |
20 | |
21 | // This tests a conforming extension |
22 | |
23 | #include <vector> |
24 | #include <utility> |
25 | #include <cassert> |
26 | |
27 | #include "test_macros.h" |
28 | #include "test_allocator.h" |
29 | |
30 | template <class T> |
31 | struct some_alloc |
32 | { |
33 | typedef T value_type; |
34 | |
35 | some_alloc() {} |
36 | some_alloc(const some_alloc&); |
37 | void deallocate(void*, unsigned) {} |
38 | |
39 | typedef std::true_type propagate_on_container_swap; |
40 | }; |
41 | |
42 | template <class T> |
43 | struct some_alloc2 |
44 | { |
45 | typedef T value_type; |
46 | |
47 | some_alloc2() {} |
48 | some_alloc2(const some_alloc2&); |
49 | void deallocate(void*, unsigned) {} |
50 | |
51 | typedef std::false_type propagate_on_container_swap; |
52 | typedef std::true_type is_always_equal; |
53 | }; |
54 | |
55 | int main(int, char**) |
56 | { |
57 | #if defined(_LIBCPP_VERSION) |
58 | { |
59 | typedef std::vector<bool> C; |
60 | static_assert(noexcept(swap(std::declval<C&>(), std::declval<C&>())), "" ); |
61 | } |
62 | { |
63 | typedef std::vector<bool, test_allocator<bool>> C; |
64 | static_assert(noexcept(swap(std::declval<C&>(), std::declval<C&>())), "" ); |
65 | } |
66 | { |
67 | typedef std::vector<bool, other_allocator<bool>> C; |
68 | static_assert(noexcept(swap(std::declval<C&>(), std::declval<C&>())), "" ); |
69 | } |
70 | #endif // _LIBCPP_VERSION |
71 | { |
72 | #if TEST_STD_VER >= 14 |
73 | #if defined(_LIBCPP_VERSION) |
74 | // In C++14, if POCS is set, swapping the allocator is required not to throw |
75 | typedef std::vector<bool, some_alloc<bool>> C; |
76 | static_assert( noexcept(swap(std::declval<C&>(), std::declval<C&>())), "" ); |
77 | #endif // _LIBCPP_VERSION |
78 | #else |
79 | typedef std::vector<bool, some_alloc<bool>> C; |
80 | static_assert(!noexcept(swap(x&: std::declval<C&>(), y&: std::declval<C&>())), "" ); |
81 | #endif |
82 | } |
83 | #if TEST_STD_VER >= 14 |
84 | #if defined(_LIBCPP_VERSION) |
85 | { |
86 | typedef std::vector<bool, some_alloc2<bool>> C; |
87 | // if the allocators are always equal, then the swap can be noexcept |
88 | static_assert( noexcept(swap(std::declval<C&>(), std::declval<C&>())), "" ); |
89 | } |
90 | #endif // _LIBCPP_VERSION |
91 | #endif |
92 | |
93 | return 0; |
94 | } |
95 | |