One way is to insert file name and line number strings (via pointer) of the module allocating memory into the allocated block of data. The file and line number is handled by using the C++ standard "__FILE__" and "__LINE__" macros. When the memory is de-allocated, that information is removed.

One of our systems has this feature and we call it a "memory hog report". So anytime from our CLI we can print out all the allocated memory along with a big list of information of who has allocated memory. This list is sorted by which code module has the most memory allocated. Many times we'll monitor memory usage this way over time, and eventually the memory hog (leak) will bubble up to the top of the list.