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, c++17
10
11 // enum class endian;
12 // <bit>
13
14 #include <bit>
15 #include <cassert>
16 #include <cstdint>
17 #include <cstring>
18 #include <type_traits>
19
20 #include "test_macros.h"
21
main(int,char **)22 int main(int, char**) {
23 static_assert(std::is_enum<std::endian>::value, "");
24
25 // Check that E is a scoped enum by checking for conversions.
26 typedef std::underlying_type<std::endian>::type UT;
27 static_assert(!std::is_convertible<std::endian, UT>::value, "");
28
29 // test that the enumeration values exist
30 static_assert( std::endian::little == std::endian::little );
31 static_assert( std::endian::big == std::endian::big );
32 static_assert( std::endian::native == std::endian::native );
33 static_assert( std::endian::little != std::endian::big );
34
35 // Technically not required, but true on all existing machines
36 static_assert( std::endian::native == std::endian::little ||
37 std::endian::native == std::endian::big );
38
39 // Try to check at runtime
40 {
41 std::uint32_t i = 0x01020304;
42 char c[4];
43 static_assert(sizeof(i) == sizeof(c));
44 std::memcpy(c, &i, sizeof(c));
45
46 assert ((c[0] == 1) == (std::endian::native == std::endian::big));
47 }
48
49 return 0;
50 }
51