Why should we overload/override new and delete?

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Any reason to overload global new and delete?

Why should we overload/override new and delete in C++?

Give me an example of situation in which we should overload/override new, new[], delete or delete[].

And: http://stackoverflow.com/questions/7149461/why-should-one-replace-default-new-and-delete-operators — tinman, Sep 06 '11 at 08:25

score 2 · Answer 1 · answered Sep 06 '11 at 08:26

2

This sounds a bit like a homework assignment. Nevertheless, here are two uses off the top of my head:

For profiling purposes. For instance, we use it in a library as a poor-man’s valgrind to track memory leaks.
To implement a custom allocator (e.g. a pool allocator) for your objects. Usually I’d implement an allocator for this, though.

answered Sep 06 '11 at 08:26

Konrad Rudolph

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+1, for `poor-man’s valgrind` :)) – iammilind Sep 06 '11 at 08:32

score 0 · Answer 2 · answered Sep 06 '11 at 08:27

To provide your implementation of allocating/deallocating memory. new/delete are very general. When you know how your application is going to use memory you can provide more efficient version of new/delete. That would be very simple for example if you used a lot of small object.

Another usage would be to provide memory leak detection.

That's not very often used mechanism - at least in my experience.

Why should we overload/override new and delete?

2 Answers2