1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
|
// { dg-do run { target c++11 } }
// { dg-require-effective-target hosted }
// Copyright (C) 2008-2024 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
// 20.8.13.2 Template class shared_ptr [util.smartptr.shared]
#include <memory>
#include <testsuite_hooks.h>
struct A { };
namespace std
{
template<>
struct less<A*>
{
static int count;
bool operator()(A* l, A* r) { ++count; return l < r; }
};
int less<A*>::count = 0;
}
// 20.8.13.2.7 shared_ptr comparison [util.smartptr.shared.cmp]
int
test01()
{
std::less<std::shared_ptr<A>> less;
// test empty shared_ptrs compare equivalent
std::shared_ptr<A> p1;
std::shared_ptr<A> p2;
VERIFY( !less(p1, p2) && !less(p2, p1) );
#ifndef __cpp_lib_three_way_comparison
// In C++20 std::less<std::shared_ptr<A>> uses the operator< synthesized
// from operator<=>, which uses std::compare_three_way not std::less<A*>.
VERIFY( std::less<A*>::count == 2 );
#endif
return 0;
}
// Construction from pointer
int
test02()
{
std::less<std::shared_ptr<A>> less;
std::shared_ptr<A> empty;
std::shared_ptr<A> p1(new A);
std::shared_ptr<A> p2(new A);
VERIFY( less(p1, p2) || less(p2, p1) );
VERIFY( !(less(p1, p2) && less(p2, p1)) );
p1.reset();
VERIFY( !less(p1, empty) && !less(empty, p1) );
p2.reset();
VERIFY( !less(p1, p2) && !less(p2, p1) );
return 0;
}
// Aliasing
int
test03()
{
std::less<std::shared_ptr<A>> less;
A a;
std::shared_ptr<A> p1(new A);
std::shared_ptr<A> p2(p1, &a);
VERIFY( less(p1, p2) || less(p2, p1) );
return 0;
}
int
main()
{
test01();
test02();
test03();
return 0;
}
|
