Is the correct type required for the delete operator in C++?

Question

void * intptr = new int;
delete (int *) intptr;

Is the (int *) type cast required?

Answer 1

Yes.

The type must match that which was new'd. The only time it doesn't have to match is deletion of a derived type through a base pointer, where the base type has a virtual destructor.

Answer 2

Yes. Since C++ is not an everything-is-and-object language, the delete command must know the type of what you want to delete in order to know how to delete it.

Answer 3

3 destructors for int will be called.

There's no such thing as a "destructor for int". delete/delete[] will only call a destructor for things that aren't POD or POD-class types.