How to create a memory leak in C++?

Question

I was just wondering how you could create a system memory leak using C++. I have done some googling on this but not much came up, I am aware that it is not really feasible t

Answer 1

There are many kinds of memory leaks:

• Allocated memory that is unreleasable because nothing points to it.
  These kind of leaks are easy to create in C and C++. They are also pretty easy to prevent, easy to detect, and easy to cure. Because they are easy to detect there are lots of tools, free and commercial, to help find such leaks.

• Still-accessible allocated memory that should have been released a long time ago.
  These kinds of leaks are much harder to detect, prevent, or cure. Something still points to it, and it will be released eventually -- for example, right before exit(). Technically speaking, this isn't quite a leak, but for all practical purposes it is a leak. Lots of supposedly leak-free applications have such leaks. All you have to do is run a system profile to see some silly application consume ever more memory. These kinds of leaks are easy to create even in managed languages.

• Allocated memory that should never have been allocated in the first place.
  Example: A user can easily ask Matlab to creating these kinds of leaks. Matlab is also rather aggressive at creating these kinds of leaks. When Matlab gets a failure from malloc it goes into a loop where it waits for a bit and then retries the malloc. Meanwhile, the OS frantically tries to deal with the loss of memory by shuffling chunks of programs from real memory into virtual memory. Eventually everything is in virtual memory -- and everything creeps to a standstill.