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 // <memory> 11 12 // shared_ptr 13 14 // template <class T> 15 // bool 16 // atomic_compare_exchange_weak(shared_ptr<T>* p, shared_ptr<T>* v, 17 // shared_ptr<T> w); 18 19 #include <memory> 20 #include <cassert> 21 22 int main() 23 { 24 #if __has_feature(cxx_atomic) 25 { 26 std::shared_ptr<int> p(new int(4)); 27 std::shared_ptr<int> v(new int(3)); 28 std::shared_ptr<int> w(new int(2)); 29 bool b = std::atomic_compare_exchange_weak(&p, &v, w); 30 assert(b == false); 31 assert(*p == 4); 32 assert(*v == 4); 33 assert(*w == 2); 34 } 35 { 36 std::shared_ptr<int> p(new int(4)); 37 std::shared_ptr<int> v = p; 38 std::shared_ptr<int> w(new int(2)); 39 bool b = std::atomic_compare_exchange_weak(&p, &v, w); 40 assert(b == true); 41 assert(*p == 2); 42 assert(*v == 4); 43 assert(*w == 2); 44 } 45 #endif 46 } 47
