App crashes but only when it's build for Ad-Hoc distro

Question

My problem is this. I have an app that builds and runs fine in Debug mode, no crashes, memory errors, etc. As soon as I do an Ad-hoc build and try to run it on the device the main thread crashes at a certain point, for no apparent reason... The stack trace I managed to get from the device log is thus...

0   libSystem.B.dylib               0x30d7c2d4 __kill + 8
1   libSystem.B.dylib               0x30d7c2c4 kill + 4
2   libSystem.B.dylib               0x30d7c2b6 raise + 10
3   libSystem.B.dylib               0x30d90d72 abort + 50
4   libstdc++.6.dylib               0x34981a20 __gnu_cxx::__verbose_terminate_handler() + 376
5   libobjc.A.dylib                 0x34a83594 _objc_terminate + 104
6   libstdc++.6.dylib               0x3497fdf2 __cxxabiv1::__terminate(void (*)()) + 46
7   libstdc++.6.dylib               0x3497fe46 std::terminate() + 10
8   libstdc++.6.dylib               0x3497ff16 __cxa_throw + 78
9   libobjc.A.dylib                 0x34a824c4 objc_exception_throw + 64
10  CoreFoundation                  0x3587a7c2 +[NSException raise:format:arguments:] + 62
11  CoreFoundation                  0x3587a7fc +[NSException raise:format:] + 28
12  QuartzCore                      0x31071222 CALayerSetPosition(CALayer*, CA::Vec2<double> const&, bool) + 134
13  QuartzCore                      0x31071190 -[CALayer setPosition:] + 32
14  UIKit                           0x341e4378 -[UIView(Geometry) setCenter:] + 16
15  MyApp                           0x00012b2c 0x1000 + 72492
16  MyApp                           0x0001276a 0x1000 + 71530
17  UIKit                           0x341e3270 -[UIViewController view] + 104
18  UIKit                           0x341efd04 -[UIViewController contentScrollView] + 16
19  UIKit                           0x341efb74 -[UINavigationController _computeAndApplyScrollContentInsetDeltaForViewController:] + 24
20  UIKit                           0x341efa72 -[UINavigationController _layoutViewController:] + 18
21  UIKit                           0x341ef4cc -[UINavigationController _startTransition:fromViewController:toViewController:] + 248
22  UIKit                           0x341ef358 -[UINavigationController _startDeferredTransitionIfNeeded] + 176
23  UIKit                           0x341e30be -[UINavigationController pushViewController:transition:forceImmediate:] + 634
24  UIKit                           0x341e2e34 -[UINavigationController pushViewController:animated:] + 28
25  MyApp                           0x00004f80 0x1000 + 16256
26  UIKit                           0x3420b834 -[UITableView _selectRowAtIndexPath:animated:scrollPosition:notifyDelegate:] + 656
27  UIKit                           0x342cb60c -[UITableView _userSelectRowAtPendingSelectionIndexPath:] + 124
28  Foundation                      0x31181df6 __NSFireDelayedPerform + 362
29  CoreFoundation                  0x3583109c __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 8
30  CoreFoundation                  0x35830b54 __CFRunLoopDoTimer + 844
31  CoreFoundation                  0x358021ae __CFRunLoopRun + 1082
32  CoreFoundation                  0x35801c80 CFRunLoopRunSpecific + 224
33  CoreFoundation                  0x35801b88 CFRunLoopRunInMode + 52
34  GraphicsServices                0x320c84a4 GSEventRunModal + 108
35  GraphicsServices                0x320c8550 GSEventRun + 56
36  UIKit                           0x341dc322 -[UIApplication _run] + 406
37  UIKit                           0x341d9e8c UIApplicationMain + 664

The other really strange thing is that if you close the app and stop it running (after the crash) in the background and then relaunch it, it bails out almost immediately quoting...

<Warning>: Application 'MyApp' exited abnormally with signal 11: Segmentation fault

Which I'm lead to believe is a memory access error (uninitialised memory access). I'm not doing anything crazy with pointers or anything so all I can presume is that it's a problem with the CF libraries...

Any thoughts or help would be HUGELY appreciated :)

Answer 1

It's hard to say exactly what the answer is without knowing more, but my first guess is that you are providing some invalid value to a UIView's center property.

There are two pieces of information missing that could help you/me find the answer.

First, lines like these in the stack trace need to be symbolicated:

15  MyApp                           0x00012b2c 0x1000 + 72492
16  MyApp                           0x0001276a 0x1000 + 71530

Knowing what is happening in those two lines will help you track it down, and knowing what the exception that got thrown (starting at line 11 in the stack trace) contains will help further. You may be able to get this information from looking at the device's Console output in Xcode's Organizer.

You can symbolicate the crash report if you have the dSYM file that was created when you built the app for AdHoc distribution. Dragging the crash report into Xcode's Organizer window will attempt to symbolicate it automatically. If that doesn't work, you can try using the symbolicatecrash script directly. It's tucked away in a path like this:

/Developer/Platforms/iPhoneOS.platform/Developer/Library/PrivateFrameworks/DTDeviceKit.framework/Versions/A/Resources/symbolicatecrash