C ++，在堆上创建的对象与本地对象-返回指针时 [英] c++, object created on the heap vs. local - when returning a pointer

问题描述

这是来自的后续问题 >在C#中安全而不在C ++中简单指针/引用的返回，

This is a follow up question from Safe in C# not in C++, simple return of pointer / reference,

这是

person* NewPerson(void)
{
  person p;
  /* ... */
  return &p; //return pointer to person.
}

和?

person* NewPerson(void)
{
  person* pp = new person;

  return pp; //return pointer to person.
}

我知道第一个是一个坏主意，因为它将是一个疯狂的指针. 在第二种情况下，对象在堆上是否安全-就像在C#中一样 上次引用到达时超出范围了吗?

I know that the first one is a bad idea, because it will be a wild pointer. In the second case, will the object be safe on the heap - and like in c# go out of scope when the last reference is gone to it?

推荐答案

这是安全的，返回后该对象仍将保持活动状态.

It's safe, the object will still be alive after the return.

但是不要期望在C ++中为您自动清除对象.标准C ++没有垃圾回收.您需要自己delete该对象，或使用某种形式的智能指针.

But don't expect the object to be automatically cleaned up for you in C++. Standard C++ does not have garbage collection. You'll need to delete the object yourself, or use some form of smart pointer.

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