std::declare_reachable

 

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定义在头文件 <memory> 中
void declare_reachable( void* p );		(自 C++11 起) (在 C++23 中移除)

声明由指针 p 引用的对象可达。即使所有指向它的指针都被销毁，可达对象也不会被垃圾收集器删除，也不会被泄漏检测器认为是泄漏。一个对象可以多次声明为可达，在这种情况下，需要多次调用 std::undeclare_reachable 来移除此属性。例如，如果实现启用了垃圾回收，那么 异或链表 需要声明其节点可达。

参数

p

-

一个安全派生的指针或空指针

返回值

(无)

异常

如果系统无法分配跟踪可达对象所需的内存，可能会抛出 std::bad_alloc。

另请参阅

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

声明一个对象可以被回收 (函数模板)