std::declare_reachable

 

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在标头 <memory> 定义
void declare_reachable( void* p );		(C++11 起) (C++23 中移除)

声明 p 所引用的对象可抵达。可抵达对象将不为垃圾收集器删除，或不被泄漏检测器认为是泄露，即使所有指向它的指针都被销毁。对象可以声明为多次可抵达，该情况下会需要多次调用 std::undeclare_reachable 以移除此属性。例如，若实现拥有启用的垃圾收集，则异或链表需要声明其结点为可抵达。

参数

p

-

安全派生的指针或空指针

返回值

（无）

异常

若系统不能分配追踪可抵达对象所要求的内存，则可能抛出 std::bad_alloc。

参阅

undeclare_reachable (C++11)(C++23 中移除)

声明一个对象可以被回收 (函数模板)