Here's a quick and easy solution (Score 2, Informative)

Write a malloc wrapper and #define it in place of the real thing. With #define you can easily log the location in the code, amount of RAM, and location in memory to a file, then write a script in the language of your choice to see which locations in RAM weren't dealloced, and match them with the appropriate malloc call, which also contains the location in code. It took me about an hour to implement this in a multi-thousand line program and it works very well. The only thing it doesn't catch is when a library call mallocs something and expects you to dealloc it, but i solved this by including a fake malloc call that just logs but doesn't actually malloc, so you'd call it right after the library call that actually does the malloc.