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// <utility>
10
11// template <class T1, class T2> struct pair
12
13// explicit(see-below) constexpr pair();
14
15// NOTE: The SFINAE on the default constructor is tested in
16// default-sfinae.pass.cpp
17
18#include <utility>
19#include <type_traits>
20#include <cassert>
21
22#include "test_macros.h"
23#include "archetypes.h"
24
25int main(int, char**) {
26 {
27 typedef std::pair<float, short*> P;
28 P p;
29 assert(p.first == 0.0f);
30 assert(p.second == nullptr);
31 }
32#if TEST_STD_VER >= 11
33 {
34 typedef std::pair<float, short*> P;
35 constexpr P p;
36 static_assert(p.first == 0.0f, "");
37 static_assert(p.second == nullptr, "");
38 }
39 {
40 using NoDefault = ImplicitTypes::NoDefault;
41 using P = std::pair<int, NoDefault>;
42 static_assert(!std::is_default_constructible<P>::value, "");
43 using P2 = std::pair<NoDefault, int>;
44 static_assert(!std::is_default_constructible<P2>::value, "");
45 }
46 {
47 struct Base {};
48 struct Derived : Base {
49 protected:
50 Derived() = default;
51 };
52 static_assert(!std::is_default_constructible<std::pair<Derived, int> >::value, "");
53 }
54#endif
55
56 return 0;
57}
58

source code of libcxx/test/std/utilities/utility/pairs/pairs.pair/ctor.default.pass.cpp