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 
11 // type_traits
12 
13 // has_unique_object_representations
14 
15 #include <type_traits>
16 
17 #include "test_macros.h"
18 
19 template <class T>
test_has_unique_object_representations()20 void test_has_unique_object_representations()
21 {
22     static_assert( std::has_unique_object_representations<T>::value, "");
23     static_assert( std::has_unique_object_representations<const T>::value, "");
24     static_assert( std::has_unique_object_representations<volatile T>::value, "");
25     static_assert( std::has_unique_object_representations<const volatile T>::value, "");
26 
27     static_assert( std::has_unique_object_representations_v<T>, "");
28     static_assert( std::has_unique_object_representations_v<const T>, "");
29     static_assert( std::has_unique_object_representations_v<volatile T>, "");
30     static_assert( std::has_unique_object_representations_v<const volatile T>, "");
31 }
32 
33 template <class T>
test_has_not_has_unique_object_representations()34 void test_has_not_has_unique_object_representations()
35 {
36     static_assert(!std::has_unique_object_representations<T>::value, "");
37     static_assert(!std::has_unique_object_representations<const T>::value, "");
38     static_assert(!std::has_unique_object_representations<volatile T>::value, "");
39     static_assert(!std::has_unique_object_representations<const volatile T>::value, "");
40 
41     static_assert(!std::has_unique_object_representations_v<T>, "");
42     static_assert(!std::has_unique_object_representations_v<const T>, "");
43     static_assert(!std::has_unique_object_representations_v<volatile T>, "");
44     static_assert(!std::has_unique_object_representations_v<const volatile T>, "");
45 }
46 
47 class Empty
48 {
49 };
50 
51 class NotEmpty
52 {
53     virtual ~NotEmpty();
54 };
55 
56 union EmptyUnion {};
57 struct NonEmptyUnion {int x; unsigned y;};
58 
59 struct bit_zero
60 {
61     int :  0;
62 };
63 
64 class Abstract
65 {
66     virtual ~Abstract() = 0;
67 };
68 
69 struct A
70 {
71     ~A();
72     unsigned foo;
73 };
74 
75 struct B
76 {
77    char bar;
78    int foo;
79 };
80 
81 
main(int,char **)82 int main(int, char**)
83 {
84     test_has_not_has_unique_object_representations<void>();
85     test_has_not_has_unique_object_representations<Empty>();
86     test_has_not_has_unique_object_representations<EmptyUnion>();
87     test_has_not_has_unique_object_representations<NotEmpty>();
88     test_has_not_has_unique_object_representations<bit_zero>();
89     test_has_not_has_unique_object_representations<Abstract>();
90     test_has_not_has_unique_object_representations<B>();
91 
92 //  I would expect all three of these to have unique representations.
93 //  I would also expect that there are systems where they do not.
94 //     test_has_not_has_unique_object_representations<int&>();
95 //     test_has_not_has_unique_object_representations<int *>();
96 //     test_has_not_has_unique_object_representations<double>();
97 
98 
99     test_has_unique_object_representations<unsigned>();
100     test_has_unique_object_representations<NonEmptyUnion>();
101     test_has_unique_object_representations<char[3]>();
102     test_has_unique_object_representations<char[]>();
103 
104 
105   return 0;
106 }
107