determining what originated a crash in my code - ios

Question

I'm getting crashes in a user's device (I see it in Crashalytics)
The thing is that the core dump is all iOS internal stuff.
How can I see what peice of my code originated the draw that made the crash?
Terminating app due to an uncaught exception 'NSInvalidArgumentException', reason: '-[NSAttributeDictionary textContainerForAttributedString:containerSize:lineFragmentPadding:]: unrecognized selector sent to instance 0x15dc7f20'
0 CoreFoundation 0x30065f23 +154
1 libobjc.A.dylib 0x3a7fcce7 objc_exception_throw+38
2 CoreFoundation 0x30069837 +202
3 CoreFoundation 0x30068137 +706
4 CoreFoundation 0x2ffb7098 _CF_forwarding_prep_0+24
5 UIFoundation 0x37ce5915 +12252
6 UIFoundation 0x37ce2863 +150
7 UIKit 0x328ae2c9 +4224
8 UIKit 0x32914709 +500
9 UIKit 0x3291450b +78
10 UIKit 0x329144a9 +372
11 QuartzCore 0x32540189 +100
12 QuartzCore 0x32529c5b +1858
13 QuartzCore 0x32605c1d +52
14 QuartzCore 0x3252950b +82
15 QuartzCore 0x325291bf +1118
16 QuartzCore 0x3250cd41 +208
17 QuartzCore 0x3250c9d9 +24
18 QuartzCore 0x3250c3e5 +228
19 QuartzCore 0x3250c1f7 +314
20 QuartzCore 0x325398e3 +162
21 libsystem_pthread.dylib 0x3ae176d1 +164
22 libsystem_pthread.dylib 0x3ae17453 +86
23 libsystem_pthread.dylib 0x3ae181b9 pthread_exit+28
24 Foundation 0x309a2703 +10
25 Foundation 0x30a4ea2d +1092
26 libsystem_pthread.dylib 0x3ae18959 +140
27 libsystem_pthread.dylib 0x3ae188cb _pthread_start+102
** Edit **
A different thread that crashed in this run (which again gives me no hints to the original point in my code)
Thread : Crashed: Thread
0 libsystem_c.dylib 0x3ad6206a __abort + 101
1 libsystem_c.dylib 0x3ad6206b __abort + 102
2 libsystem_c.dylib 0x3ad62005 __abort
3 libc++abi.dylib 0x3a1b098f abort_message + 74
4 libc++abi.dylib 0x3a1c96e7 default_terminate_handler() + 254
5 libobjc.A.dylib 0x3a7fcf7d _objc_terminate() + 192
6 libc++abi.dylib 0x3a1c71b3 std::__terminate(void (*)()) + 78
7 libc++abi.dylib 0x3a1c6a09 __cxxabiv1::exception_cleanup_func(_Unwind_Reason_Code, _Unwind_Exception*)
8 libobjc.A.dylib 0x3a7fcdbb objc_exception_throw + 250
9 CoreFoundation 0x30069837 -[NSObject(NSObject) doesNotRecognizeSelector:] + 202
10 CoreFoundation 0x30068137 ___forwarding___ + 706
11 CoreFoundation 0x2ffb7098 _CF_forwarding_prep_0 + 24
12 UIFoundation 0x37ce5915 __NSStringDrawingEngine + 12252
13 UIFoundation 0x37ce2863 -[NSString(NSExtendedStringDrawing) drawWithRect:options:attributes:context:] + 150
14 UIKit 0x328ae2c9 -[UILabel _drawTextInRect:baselineCalculationOnly:] + 4224
15 UIKit 0x32914709 -[UILabel drawTextInRect:] + 500
16 UIKit 0x3291450b -[UILabel drawRect:] + 78
17 UIKit 0x329144a9 -[UIView(CALayerDelegate) drawLayer:inContext:] + 372
18 QuartzCore 0x32540189 -[CALayer drawInContext:] + 100
19 QuartzCore 0x32529c5b CABackingStoreUpdate_ + 1858
20 QuartzCore 0x32605c1d ___ZN2CA5Layer8display_Ev_block_invoke + 52
21 QuartzCore 0x3252950b x_blame_allocations + 82
22 QuartzCore 0x325291bf CA::Layer::display_() + 1118
23 QuartzCore 0x3250cd41 CA::Layer::display_if_needed(CA::Transaction*) + 208
24 QuartzCore 0x3250c9d9 CA::Layer::layout_and_display_if_needed(CA::Transaction*) + 24
25 QuartzCore 0x3250c3e5 CA::Context::commit_transaction(CA::Transaction*) + 228
26 QuartzCore 0x3250c1f7 CA::Transaction::commit() + 314
27 QuartzCore 0x325398e3 CA::Transaction::release_thread(void*) + 162
28 libsystem_pthread.dylib 0x3ae176d1 _pthread_tsd_cleanup + 164
29 libsystem_pthread.dylib 0x3ae17453 _pthread_exit + 86
30 libsystem_pthread.dylib 0x3ae181b9 pthread_exit + 28
31 Foundation 0x309a2703 +[NSThread exit] + 10
32 Foundation 0x30a4ea2d __NSThread__main__ + 1092
33 libsystem_pthread.dylib 0x3ae18959 _pthread_body + 140
34 libsystem_pthread.dylib 0x3ae188cb _pthread_start + 102

Answer 1

What's unusual is that you are only getting this crash in production and not in development. That's probably due to poor testing, however another possible reason is making assumptions about the type of data you are working with, and this data is difficult to replicate in development.
JSON is a common and classic example of this, where a server can provide a string response that is magically turned into a hierarchy of objects. The code then assumes the top-level objects is a dictionary or array and starts calling methods which are unrecognised.
In your case though, you are not testing properly before release.
(this doesn't really provide an answer, but I feel you have everything you need to provide yourself with the answer, if you can be bothered to use it).