std::undeclare_reachable

 

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在标头 <memory> 定义
template< class T > T* undeclare_reachable( T* p );		(C++11 起) (C++23 中移除)

移除指针 p 所引用对象的可抵达状态，若先前为 std::declare_reachable 所设。若多次声明对象为可抵达，则需要相等次数的到 undeclare_reachable 的调用移除此属性。一旦对象不再声明为可抵达，且没有指针引用它，则它可能为垃圾收集器所回收，或被泄露检测器报告为泄露。

参数

p

-

指向先前声明为可抵达且之后未被析构的对象的指针

返回值

p 的安全派生副本。

异常

不抛出。

参阅

declare_reachable (C++11)(C++23 中移除)

声明一个对象不能被回收 (函数)