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
10// TODO: Change to XFAIL once https://github.com/llvm/llvm-project/issues/40340 is fixed
11// UNSUPPORTED: availability-pmr-missing
12
13// <memory_resource>
14
15// template <class T> class polymorphic_allocator
16
17// template <class U1, class U2>
18// void polymorphic_allocator<T>::construct(pair<U1, U2>*)
19
20#include <memory_resource>
21#include <cassert>
22#include <tuple>
23#include <type_traits>
24#include <utility>
25#include "uses_alloc_types.h"
26
27int constructed = 0;
28
29template <int>
30struct default_constructible {
31 default_constructible() : x(42) { ++constructed; }
32 int x = 0;
33};
34
35int main(int, char**) {
36 // pair<default_constructible, default_constructible>
37 {
38 typedef default_constructible<0> T;
39 typedef std::pair<T, T> P;
40 typedef std::pmr::polymorphic_allocator<void> A;
41 alignas(P) char buffer[sizeof(P)];
42 P* ptr = reinterpret_cast<P*>(buffer);
43 A a;
44 constructed = 0;
45 a.construct(p: ptr);
46 assert(constructed == 2);
47 assert(ptr->first.x == 42);
48 assert(ptr->second.x == 42);
49 }
50
51 // pair<default_constructible<0>, default_constructible<1>>
52 {
53 typedef default_constructible<0> T;
54 typedef default_constructible<1> U;
55 typedef std::pair<T, U> P;
56 typedef std::pmr::polymorphic_allocator<void> A;
57 alignas(P) char buffer[sizeof(P)];
58 P* ptr = reinterpret_cast<P*>(buffer);
59 A a;
60 constructed = 0;
61 a.construct(p: ptr);
62 assert(constructed == 2);
63 assert(ptr->first.x == 42);
64 assert(ptr->second.x == 42);
65 }
66
67 return 0;
68}
69

source code of libcxx/test/std/utilities/utility/mem.res/mem.poly.allocator.class/mem.poly.allocator.mem/construct_pair.pass.cpp