std::undeclare_reachable

 

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定义在头文件 <memory> 中
template< class T > T* undeclare_reachable( T* p );		(自 C++11 起) (在 C++23 中已移除)

如果之前通过 std::declare_reachable 设置了对象的可达状态，则删除指针 p 所引用的对象的此状态。如果该对象被多次声明为可达，则需要对 undeclare_reachable 进行相同次数的调用来删除此状态。一旦对象不再被声明为可达，并且没有指针引用它，它可能会被垃圾收集器回收，或被内存泄漏检测器报告为泄漏。

参数

p

-

指向之前声明为可达且自那时起未被销毁的对象的指针

返回值

一个从 p 安全派生的副本。

异常

不抛出任何异常。

另请参阅

declare_reachable (C++11)(在 C++23 中已移除)

声明一个对象不能被回收 (函数)