1 // Copyright (C) 2016-2018 Free Software Foundation, Inc.
2 //
3 // This file is part of the GNU ISO C++ Library. This library is free
4 // software; you can redistribute it and/or modify it under the
5 // terms of the GNU General Public License as published by the
6 // Free Software Foundation; either version 3, or (at your option)
7 // any later version.
8
9 // This library is distributed in the hope that it will be useful,
10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 // GNU General Public License for more details.
13
14 // You should have received a copy of the GNU General Public License along
15 // with this library; see the file COPYING3. If not see
16 // <http://www.gnu.org/licenses/>.
17
18 // { dg-do compile { target c++11 } }
19
20 #include <memory>
21
22 template<typename T, typename From>
can_assign()23 constexpr bool can_assign()
24 { return std::is_assignable<std::shared_ptr<T>, From>::value; }
25
26 struct Base { };
27 struct Derived : Base { };
28
29 // Positive cases:
30
31 static_assert( can_assign<const void, const std::shared_ptr<void>&>(),
32 "void* convertible to const void*");
33 static_assert( can_assign<const void, std::shared_ptr<void>&&>(),
34 "void* convertible to const void*");
35 static_assert( can_assign<const int, std::shared_ptr<int>>(),
36 "int* convertible to const int*");
37 static_assert( can_assign<Base, std::shared_ptr<Derived>>(),
38 "Derived* convertible to Base*");
39 static_assert( can_assign<const Base, std::shared_ptr<Derived>>(),
40 "Derived* convertible to const Base*");
41
42 // Negative cases:
43
44 static_assert( !can_assign<int, const std::shared_ptr<void>&>(),
45 "void* not convertible to int*");
46 static_assert( !can_assign<int, std::shared_ptr<void>&&>(),
47 "void* not convertible to int*");
48
49 static_assert( !can_assign<int, const std::shared_ptr<const int>&>(),
50 "const int* not convertible to int*");
51 static_assert( !can_assign<int, std::shared_ptr<const int>&&>(),
52 "const int* not convertible to int*");
53
54 static_assert( !can_assign<int, const std::shared_ptr<long>&>(),
55 "long* not convertible to int*");
56 static_assert( !can_assign<int, std::shared_ptr<long>&&>(),
57 "long* not convertible to int*");
58
59 static_assert( !can_assign<int, std::unique_ptr<long>&&>(),
60 "unique_ptr<long>::pointer not convertible to int*");
61
62 static_assert( !can_assign<Derived, const std::shared_ptr<Base>&>(),
63 "Base* not convertible to Derived*");
64 static_assert( !can_assign<int, std::shared_ptr<long>&&>(),
65 "Base* not convertible to Derived*");
66 static_assert( !can_assign<Derived, std::unique_ptr<Base>&&>(),
67 "unique_ptr<Base>::pointer not convertible to Derived*");
68
69 struct Deleter {
70 using pointer = void*;
operator ()Deleter71 void operator()(pointer) const { }
72 };
73
74 static_assert( !can_assign<Derived, std::unique_ptr<Derived, Deleter>&&>(),
75 "unique_ptr<Derived, Deleter>::pointer not convertible to Derived*");
76