Question

If it is known that an application leaks memory (when executed), what are the various ways to locate such memory leak bugs in the source code of the application.
I know of certain parsers/tools (which probably do static analysis of the code) which can be used here but are there any other ways/techniques to do that, specific to the language (C/C++)/platform?

Answer 1

There’s valgrind and probably other great tools out there.
But I’ll tell you what I do, that works very well for me, given that many times I code in environments where you can’t run valgrind:

• Be sure to pair each allocation with a deallocation. I always count news or mallocs and search for the delete or free.
• If in C++ and using exceptions, try to put them paired on constructors/destructors. If you like risk, or can’t put them in Ctor/dtor, be sure no exception can make the program flow not to execute the deallocation.
• Use of smart pointers and ptr containers.
• One can monitor alloc/dealloc rewriting new or installing a malloc handler. At some point, if the code runs continuously it can be obvious if the memory usage becomes stationary and doesn’t grow without bounds which would be the worst case of leak.
• Be careful with containers that never shrink such as vectors. There are tricks to shrink them swapping them with an empty container.