1 //===----------------------------------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // UNSUPPORTED: libcpp-has-no-threads
11 //  ... assertion fails line 34
12 
13 // <atomic>
14 
15 // template <class T>
16 //     bool
17 //     atomic_compare_exchange_strong(volatile atomic<T>* obj, T* expc, T desr);
18 //
19 // template <class T>
20 //     bool
21 //     atomic_compare_exchange_strong(atomic<T>* obj, T* expc, T desr);
22 
23 #include <atomic>
24 #include <type_traits>
25 #include <cassert>
26 
27 #include "atomic_helpers.h"
28 
29 template <class T>
30 struct TestFn {
31   void operator()() const {
32     {
33         typedef std::atomic<T> A;
34         A a;
35         T t(T(1));
36         std::atomic_init(&a, t);
37         assert(std::atomic_compare_exchange_strong(&a, &t, T(2)) == true);
38         assert(a == T(2));
39         assert(t == T(1));
40         assert(std::atomic_compare_exchange_strong(&a, &t, T(3)) == false);
41         assert(a == T(2));
42         assert(t == T(2));
43     }
44     {
45         typedef std::atomic<T> A;
46         volatile A a;
47         T t(T(1));
48         std::atomic_init(&a, t);
49         assert(std::atomic_compare_exchange_strong(&a, &t, T(2)) == true);
50         assert(a == T(2));
51         assert(t == T(1));
52         assert(std::atomic_compare_exchange_strong(&a, &t, T(3)) == false);
53         assert(a == T(2));
54         assert(t == T(2));
55     }
56   }
57 };
58 
59 int main()
60 {
61     TestEachAtomicType<TestFn>()();
62 }
63