Comment # 3 on bug 75102 from Alex Deucher

(In reply to comment #2)
> I'm at work right now, but hopefully I can supply the logs later.
> 
> How would I go about bisecting? It sounds like a nightmare, running through
> all check-ins between 3.12 and 3.13. Is there a guide, or some tips on what
> changes to check? Do I start in the middle to see if the problem is there?

Google for "git bisect howto".  Git makes it really easy.