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: libcpp-has-no-threads
10 
11 // <thread>
12 
13 // class thread
14 
15 // void swap(thread& x, thread& y);
16 
17 #include <thread>
18 #include <new>
19 #include <cstdlib>
20 #include <cassert>
21 
22 #include "test_macros.h"
23 
24 class G
25 {
26     int alive_;
27 public:
28     static int n_alive;
29     static bool op_run;
30 
31     G() : alive_(1) {++n_alive;}
32     G(const G& g) : alive_(g.alive_) {++n_alive;}
33     ~G() {alive_ = 0; --n_alive;}
34 
35     void operator()()
36     {
37         assert(alive_ == 1);
38         assert(n_alive >= 1);
39         op_run = true;
40     }
41 };
42 
43 int G::n_alive = 0;
44 bool G::op_run = false;
45 
46 int main(int, char**)
47 {
48     {
49         G g;
50         std::thread t0(g);
51         std::thread::id id0 = t0.get_id();
52         std::thread t1;
53         std::thread::id id1 = t1.get_id();
54         swap(t0, t1);
55         assert(t0.get_id() == id1);
56         assert(t1.get_id() == id0);
57         t1.join();
58     }
59 
60   return 0;
61 }
62