Can I mix new and malloc on different redirection?

Question

Is this behaviour undefined where I am mixing both new and malloc?

int main()
{
  int ***arr = new int**[1];
  arr[0] = static_cast<int**>(malloc(sizeof(int**)));
  arr[0][0] = new int; 
  arr[0][0][0] = 1;

  //now, release memory using appropriate operator
}

Just hypothetical. While reading one book I had the thought. — Sreeraj Chundayil, Aug 01 '21 at 16:51
No, it's not undefined behavior. But it is a moot point. Modern C++ rarely requires a `new` or a `malloc` of anything, in the first place. Containers will do all the memory allocations for you, correctly, and without you having to worry about memory leaks. — Sam Varshavchik, Aug 01 '21 at 16:52
I don't think it is exactly same question as duplicate. In the duplicate used variables are different. — Sreeraj Chundayil, Aug 01 '21 at 17:22

score 4 · Accepted Answer · answered Aug 01 '21 at 16:54

4

Yes, you can do that. You must call delete[], delete and free accordingly later on. Be careful to not free something you got from malloc with delete etc.

answered Aug 01 '21 at 16:54

Aykhan Hagverdili

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score 1 · Answer 2 · answered Aug 01 '21 at 16:58

1

Is this behaviour undefined where I am mixing both new and malloc?

There is no UB in the example.

You can do this, but there is no benefit.

answered Aug 01 '21 at 16:58

eerorika

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Can I mix new and malloc on different redirection?

2 Answers2