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// XFAIL: !has-64-bit-atomics
10// XFAIL: !has-1024-bit-atomics
11
12// T operator=(T) const noexcept;
13
14#include <atomic>
15#include <cassert>
16#include <concepts>
17#include <type_traits>
18
19#include "atomic_helpers.h"
20#include "test_helper.h"
21#include "test_macros.h"
22
23template <typename T>
24struct TestAssign {
25 void operator()() const {
26 {
27 T x(T(1));
28 std::atomic_ref<T> const a(x);
29
30 std::same_as<T> decltype(auto) y = (a = T(2));
31 assert(y == T(2));
32 assert(x == T(2));
33
34 ASSERT_NOEXCEPT(a = T(0));
35 static_assert(std::is_nothrow_assignable_v<std::atomic_ref<T>, T>);
36
37 static_assert(!std::is_copy_assignable_v<std::atomic_ref<T>>);
38 }
39
40 {
41 auto assign = [](std::atomic_ref<T> const& y, T, T new_val) { y = new_val; };
42 auto load = [](std::atomic_ref<T> const& y) { return y.load(); };
43 test_seq_cst<T>(assign, load);
44 }
45 }
46};
47
48int main(int, char**) {
49 TestEachAtomicType<TestAssign>()();
50 return 0;
51}
52

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