I've got a stack trace showing a crash responding to a memory warning:
Thu Oct 28 00:42:55 iPhone DTMobileIS[10853] : _memoryNotification : {name = (null), num = 1} Thu Oct 28 00:42:55 iPhone DTMobileIS[10853] : _memoryNotification : { OSMemoryNotificationLevel = 1; timestamp = "2010-10-28 07:42:55 GMT"; } Thu Oct 28 00:42:55 iPhone MyApp[11059] : Received memory warning. Level=1 Thu Oct 28 00:42:55 iPhone MyApp[11059] : -[__NSCFType tryLock]: unrecognized selector sent to instance 0x41bfd0 Thu Oct 28 00:42:55 iPhone MyApp[11059] : *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFType tryLock]: unrecognized selector sent to instance 0x41bfd0' *** Call stack at first throw: ( 0 CoreFoundation 0x30897ed3 __exceptionPreprocess + 114 1 libobjc.A.dylib 0x3002f811 objc_exception_throw + 24 2 CoreFoundation 0x30899683 -[NSObject(NSObject) doesNotRecognizeSelector:] + 102 3 CoreFoundation 0x308411d9 ___forwarding___ + 508 4 CoreFoundation 0x30840f90 _CF_forwarding_prep_0 + 48 5 CoreData 0x316cc261 -[_NSSQLCoreConnectionObsever _purgeCaches:] + 124 6 Foundation 0x349bb6b3 _nsnote_callback + 142 7 CoreFoundation 0x3081e713 __CFXNotificationPost_old + 402 8 CoreFoundation 0x3081e3b3 _CFXNotificationPostNotification + 118 9 Foundation 0x349aadb7 -[NSNotificationCenter postNotificationName:object:userInfo:] + 70 10 Foundation 0x349b42d1 -[NSNotificationCenter postNotificationName:object:] + 24 11 UIKit 0x31ed9431 -[UIApplication _performMemoryWarning] + 48 12 UIKit 0x31ec7383 -[UIApplication _receivedMemoryNotification] + 126 13 UIKit 0x31ec72c7 _memoryStatusChanged + 42 14 CoreFoundation 0x3084e825 __CFNotificationCenterDarwinCallBack + 24 15 CoreFoundation 0x30835313 __CFMachPortPerform + 210 16 CoreFoundation 0x3082cce3 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 26 17 CoreFoundation 0x3082cca7 __CFRunLoopDoSource1 + 166 18 CoreFoundation 0x3081f56d __CFRunLoopRun + 520 19 CoreFoundation 0x3081f277 CFRunLoopRunSpecific + 230 20 CoreFoundation 0x3081f17f CFRunLoopRunInMode + 58 21 GraphicsServices 0x31e445f3 GSEventRunModal + 114 22 GraphicsServices 0x31e4469f GSEventRun + 62 23 UIKit 0x31e51123 -[UIApplication _run] + 402 24 UIKit 0x31e4f12f UIApplicationMain + 670 25 MyApp 0x00052c81 main + 72 26 MyApp 0x00002f18 start + 52 )
I'm not really sure what core data was doing that it tried to obtain a lock from this object, however I feel like this is indicative of a threading issue somewhere inside my code.
Can anyone think of a good way to debug this or possible root causes?