Critique my heap debugger

Question

I wrote the following heap debugger in order to demonstrate memory leaks, double deletes and wrong forms of deletes (i.e. trying to delete an array with delete p

Answer 1

Instead of doing intrusive note-keeping you could keep a list of all allocations made. Then you can free the memory without destroying your own data, and keep track of how many times a particular address is "deleted", and also find places where the program tries to delete a non-matching address (i.e. not in the list).