Most common reasons for unstable bugs in C++?

Question

I am currently working on a large project, and I spend most of the time debugging. While debugging is a normal process, there are bugs, that are unstable, and these bugs are

Answer 1

If you are really in a position where you already have bad code that breaks, the best plan is probably to throw as many tools at it as you can (OS/lib-level memory checking, automated testing, logging, core dumps, etc) to find the problem areas. Then rewrite the code to do something more deterministic. Most of the bugs come from people doing things that mostly work most of the time, but C++ offers stronger guarantees if you use the right tools and approaches.