xref: /llvm-project/libcxx/test/std/containers/sequences/array/array.data/data_const.pass.cpp (revision 3cd4531b9ba421d1d096e746d787fe3039a546bb)
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 // <array>
10 
11 // const T* data() const;
12 
13 #include <array>
14 #include <cassert>
15 #include <cstddef>       // for std::max_align_t
16 #include <cstdint>
17 
18 #include "test_macros.h"
19 
20 struct NoDefault {
NoDefaultNoDefault21     TEST_CONSTEXPR NoDefault(int) { }
22 };
23 
24 #if TEST_STD_VER < 11
25 struct natural_alignment {
26     long t1;
27     long long t2;
28     double t3;
29     long double t4;
30 };
31 #endif
32 
tests()33 TEST_CONSTEXPR_CXX17 bool tests()
34 {
35     {
36         typedef double T;
37         typedef std::array<T, 3> C;
38         const C c = {1, 2, 3.5};
39         ASSERT_NOEXCEPT(c.data());
40         const T* p = c.data();
41         assert(p[0] == 1);
42         assert(p[1] == 2);
43         assert(p[2] == 3.5);
44     }
45     {
46         typedef double T;
47         typedef std::array<T, 0> C;
48         const C c = {};
49         ASSERT_NOEXCEPT(c.data());
50         const T* p = c.data();
51         (void)p;
52     }
53     {
54         typedef NoDefault T;
55         typedef std::array<T, 0> C;
56         const C c = {};
57         ASSERT_NOEXCEPT(c.data());
58         const T* p = c.data();
59         (void)p;
60     }
61     {
62         std::array<int, 5> const c = {0, 1, 2, 3, 4};
63         assert(c.data() == &c[0]);
64         assert(*c.data() == c[0]);
65     }
66 
67     return true;
68 }
69 
main(int,char **)70 int main(int, char**)
71 {
72     tests();
73 #if TEST_STD_VER >= 17
74     static_assert(tests(), "");
75 #endif
76 
77     // Test the alignment of data()
78     {
79 #if TEST_STD_VER < 11
80         typedef natural_alignment T;
81 #else
82         typedef std::max_align_t T;
83 #endif
84         typedef std::array<T, 0> C;
85         const C c = {};
86         const T* p = c.data();
87         std::uintptr_t pint = reinterpret_cast<std::uintptr_t>(p);
88         assert(pint % TEST_ALIGNOF(T) == 0);
89     }
90 
91     return 0;
92 }
93