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 12 // <mutex> 13 14 // struct once_flag; 15 16 // template<class Callable, class ...Args> 17 // void call_once(once_flag& flag, Callable&& func, Args&&... args); 18 19 // This test is supposed to be run with ThreadSanitizer and verifies that 20 // call_once properly synchronizes user state, a data race that was fixed 21 // in r280621. 22 23 #include <mutex> 24 #include <thread> 25 #include <cassert> 26 27 std::once_flag flg0; 28 long global = 0; 29 init0()30void init0() 31 { 32 ++global; 33 } 34 f0()35void f0() 36 { 37 std::call_once(flg0, init0); 38 assert(global == 1); 39 } 40 main()41int main() 42 { 43 std::thread t0(f0); 44 std::thread t1(f0); 45 t0.join(); 46 t1.join(); 47 assert(global == 1); 48 } 49