No and no. A8 will not fix faulty code or even damaged files which can lead to crashes too, how would it.

Memory leaks and other related crashes can be caused from of course not freeing allocated memory (i.e. you have to use sys_malloc or malloc in your code for that to happen) or overwriting stuff, for example
for(i = 0; i <= 10; i++) my_array[i] = i;
where
var my_array[10];
does not have a 10th entry. As a result you overwrite the 4 byte that follows the my_array array in your memory and all kind of weird stuff can and usually will happen.

The problem may lie somewhere completely else though too and that is a faulty file which happens more often than one would imagine. Over the years I've experienced that a few times already, and oftentimes I have to strip down my projects completely (make a backup first/ work with a backup copy) which can take a week or two. Preferably, you want to be able to delete as much as possible with the bug still intact so you can try and find its cause. Otherwise, if you only delete or change (as in your case) a little and the bug disappears it's likely you just have postponed the error to reappear at some random point in the future.
I've once had random crashes in a multiplayer skateboarding game with multiple levels, I've checked everything, my whole code over and over, stripped down the whole project only to find (with the help of jcl) that one texture in one of the levels was damaged. Then on loading erroneous stuff would happen and overwrite random areas which would lead to subsequent code crashes.