Weird iPhone app crashes on iOS 5

Question

I'm getting really strange and frequent crashes in my app that I think was working fine before I updated to iOS 5 (but I'm not 100% sure about this). Basically, the crashes frequently occur when I leave the app (press home button) and come back. It does not always crash, but frequently.

Anyone get similar crashes?

My TestFlight report reports "SIGSEGV, Unknown Signal".

When I look in my phone logs, it says:

0 ****** 0x000e7745 Vingit + 943941
1 ****** 0x000e7b5b Vingit + 944987
2 libsystem_c.dylib 0x36970539 _sigtramp + 48
3 QuartzCore 0x32843875 _ZN2CA5Layer16commit_if_neededEPNS_11TransactionEPFvPS0_jjPvES4_ +216
4 QuartzCore 0x32843875 _ZN2CA5Layer16commit_if_neededEPNS_11TransactionEPFvPS0_jjPvES4_ +216
5 QuartzCore 0x3284773b _ZN2CA7Context11commit_rootEPNS_5LayerEPv + 34
6 QuartzCore 0x32847717 _ZN2CAL16foreach_callbackEPNS_5LayerES1_Pv + 18
7 QuartzCore 0x328476ed x_hash_table_foreach + 44
8 QuartzCore 0x328476bd _ZN2CA11Transaction12foreach_rootEPFvPNS_5LayerEPvES3_ + 32
9 QuartzCore 0x32841455 _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 1052
10 QuartzCore 0x32840e57 _ZN2CA11Transaction6commitEv + 314
11 QuartzCore 0x328686f1 _ZN2CA11Transaction5flushEv + 44
12 QuartzCore 0x328686c3 +[CATransaction flush] + 34
13 UIKit 0x33168bad -[UIApplication _reportAppLaunchFinished] + 40
14 UIKit 0x33200387 -[UIApplication _handleApplicationResumeEvent:] + 1618
15 UIKit 0x33124961 -[UIApplication handleEvent:withNewEvent:] + 1080
16 UIKit 0x331243bf -[UIApplication sendEvent:] + 54
17 UIKit 0x33123d2d _UIApplicationHandleEvent + 5808
18 GraphicsServices 0x33d0fe13 PurpleEventCallback + 882
19 CoreFoundation 0x3115e553 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 38
20 CoreFoundation 0x3115e4f5 __CFRunLoopDoSource1 + 140
21 CoreFoundation 0x3115d343 __CFRunLoopRun + 1370
22 CoreFoundation 0x310e04dd CFRunLoopRunSpecific + 300
23 CoreFoundation 0x310e03a5 CFRunLoopRunInMode + 104
24 GraphicsServices 0x33d0efed GSEventRunModal + 156
25 UIKit 0x33152743 UIApplicationMain + 1090
26 ****** 0x00002dc3 main (main.m:14)
27 ****** 0x00002d6c Vingit + 7532

Answer 1

You will need to symbolicate your crash log before it makes much sense. In order for this to succeed you will need the exact same binary and dSYM file generated by the build process in Xcode. One way of ensuring this is to use the archive feature on the builds you are going to distribute to your beta testers through for instance TestFlight.

If you have done this then it should just be a matter of opening the crash log in Xcode and it will automatically locate the correct binary and dSYM file for you and convert the offset addresses in your code into method names. Hopefully that will bring you closer to the area in your code where it crashes.