I am experiencing a very strange crash, here is the backtrace.
* thread #1: tid = 0x2403, 0x3379516c CoreFoundation`CFHash + 8, stop reason = EXC_BREAKPOINT
I had / have the same problem.
The same problem occurs to me, when i present two view controllers modally above each other and want to return to the first one.
Disabling autolayout for the first presented view only solves the issue for me.
In your case self.presentingviewcontroller
Unfortunately i wasn't able to narrow it down further.