1//
2// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
3// See https://llvm.org/LICENSE.txt for license information.
4// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
5//
6//===----------------------------------------------------------------------===//
7
8// UNSUPPORTED: c++03, c++11, c++14, c++17
9
10// static constexpr size_t required_alignment;
11
12#include <atomic>
13#include <cassert>
14#include <concepts>
15#include <cstddef>
16
17template <typename T>
18constexpr void check_required_alignment() {
19 std::same_as<const std::size_t> decltype(auto) required_alignment = std::atomic_ref<T>::required_alignment;
20 assert(required_alignment >= alignof(T));
21}
22
23constexpr bool test() {
24 check_required_alignment<int>();
25 check_required_alignment<float>();
26 check_required_alignment<int*>();
27 struct Empty {};
28 check_required_alignment<Empty>();
29 struct Trivial {
30 int a;
31 };
32 check_required_alignment<Trivial>();
33 return true;
34}
35
36int main(int, char**) {
37 test();
38 static_assert(test());
39 return 0;
40}
41

source code of libcxx/test/std/atomics/atomics.ref/required_alignment.pass.cpp