C/C++ memory management - programs insanities listed

This is a continuation of my entry from several days ago view

There are different kinds of memory related issues, which usually lead to raise of a runtime error. Let's try to define categories of those:
- memory leaks - memory is being allocated and not freed, program 'grows' in context of memory usage somewhat proportionally to the time of execution, usually leads for program to become unresponsive over time. It is quite difficult to diagnose without having memory debugging monitors at your disposal.
- dereferencing nulls - we try to access memory behind the pointer which wasn't yet allocated - leads to access violation runtime error right away. Fortunately this one is fairly easy to diagnose as the cause is very close to the symptom.
- memory corruption - in our program memory there is a region which doesn't contain data we expect it does - it can be either because memory was never initialized, or because there was writing out of bounds situation on the neighboring memory region. Program now contains a 'mine' - as soon as we foot on it (by reading from corrupted memory region) we will get incorrect data fed to our program datasystem and it will start behaving inconsistently. Usually leads to runtime crash error, preceded by some strange and nondeterministic behavior in areas directly or indirectly dependent on data read from corrupted memory error. Like for the first category memory debuggers come handy here as well.