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
22int 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(dest: c, src: &i, n: sizeof(c));
45
46 assert ((c[0] == 1) == (std::endian::native == std::endian::big));
47 }
48
49 return 0;
50}
51

source code of libcxx/test/std/numerics/bit/bit.endian/endian.pass.cpp