Crash on Application Quit

Question

Can any one help me in resolving this crash. This happens when the App is quit but not always.

Application Specific Information:
objc_msgSend() selector name: respondsToSelector:
Performing @selector(terminate:) from sender NSMenuItem 0x34cfd0

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   libobjc.A.dylib                 0x979414cc objc_msgSend + 44
1   com.apple.MyApp                 0x00026d9f -[MyAppController applicationShouldTerminate:] + 398
2   com.apple.AppKit                0x91086dc2 -[NSApplication _docController:shouldTerminate:] + 83
3   com.apple.AppKit                0x91086cb4 __91-[NSDocumentController(NSInternal) _closeAllDocumentsWithDelegate:shouldTerminateSelector:]_block_invoke + 140
4   com.apple.AppKit                0x910869c0 -[NSDocumentController(NSInternal) _closeAllDocumentsWithDelegate:shouldTerminateSelector:] + 1304
5   com.apple.AppKit                0x9108646b -[NSDocumentController(NSInternal) __closeAllDocumentsWithDelegate:shouldTerminateSelector:] + 266
6   com.apple.AppKit                0x91086103 -[NSApplication _shouldTerminate] + 760
7   com.apple.AppKit                0x90f88008 -[NSApplication terminate:] + 1139
8   libobjc.A.dylib                 0x97957283 -[NSObject performSelector:withObject:] + 70
9   com.apple.AppKit                0x90f2fd75 -[NSApplication sendAction:to:from:] + 438
10  com.apple.AppKit                0x90f4c315 -[NSMenuItem _corePerformAction] + 486
11  com.apple.AppKit                0x90f4c01a -[NSCarbonMenuImpl performActionWithHighlightingForItemAtIndex:] + 163
12  com.apple.AppKit                0x90f4b6c9 -[NSMenu _performActionWithHighlightingForItemAtIndex:sendAccessibilityNotification:] + 79
13  com.apple.AppKit                0x90f4b675 -[NSMenu _performActionWithHighlightingForItemAtIndex:] + 48
14  com.apple.AppKit                0x90f4b022 -[NSMenu performKeyEquivalent:] + 294
15  com.apple.AppKit                0x90f47735 -[NSApplication _handleKeyEquivalent:] + 938
16  com.apple.AppKit                0x90eb0cbe -[NSApplication sendEvent:] + 3911
17  com.apple.AppKit                0x90cf56cc -[NSApplication run] + 823
18  com.apple.AppKit                0x90cde558 NSApplicationMain + 1165
19  com.apple.MyApp                 0x00111c9a main + 728
20  com.apple.MyApp                 0x00002401 start + 53

Some times i get the following crash logs when it is crashed on quit and this is again not always.

objc_msgSend() selector name: respondsToSelector:
objc[33814]: garbage collection is OFF

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   libobjc.A.dylib                 0x99546d47 objc_msgSend + 23
1   com.apple.MyApp                 0x0001c574 -[MyAppController applicationShouldTerminate:] + 390
2   com.apple.AppKit                0x915f6701 -[NSApplication _docController:shouldTerminate:] + 83
3   com.apple.AppKit                0x917240ff __-[NSDocumentController(NSInternal) _closeAllDocumentsWithDelegate:shouldTerminateSelector:]_block_invoke_1 + 228
4   com.apple.AppKit                0x91730f86 -[NSDocumentController(NSInternal) _closeAllDocumentsWithDelegate:shouldTerminateSelector:] + 1693
5   com.apple.AppKit                0x91729ec6 -[NSDocumentController(NSInternal) __closeAllDocumentsWithDelegate:shouldTerminateSelector:] + 310
6   com.apple.AppKit                0x915fdb15 -[NSApplication _shouldTerminate] + 889
7   com.apple.AppKit                0x91334332 -[NSApplication terminate:] + 1219
8   com.apple.CoreFoundation        0x90c1dd11 -[NSObject performSelector:withObject:] + 65
9   com.apple.AppKit                0x914371ff -[NSApplication sendAction:to:from:] + 232
10  com.apple.AppKit                0x9152ad8b -[NSMenuItem _corePerformAction] + 536
11  com.apple.AppKit                0x9152aa08 -[NSCarbonMenuImpl performActionWithHighlightingForItemAtIndex:] + 171
12  com.apple.AppKit                0x9152a091 -[NSMenu _performActionWithHighlightingForItemAtIndex:sendAccessibilityNotification:] + 79
13  com.apple.AppKit                0x9152a03d -[NSMenu _performActionWithHighlightingForItemAtIndex:] + 48
14  com.apple.AppKit                0x914a3923 -[NSMenu performKeyEquivalent:] + 306
15  com.apple.AppKit                0x914a2392 -[NSApplication _handleKeyEquivalent:] + 594
16  com.apple.AppKit                0x91397cef -[NSApplication sendEvent:] + 5772
17  com.apple.AppKit                0x91329459 -[NSApplication run] + 1007
18  com.apple.AppKit                0x915babf1 NSApplicationMain + 1054
19  com.apple.MyApp                 0x0010094b main + 216
20  com.apple.MyApp                 0x0000264d start + 53

Answer 1

The first place to look of course is in your -[MyAppController applicationShouldTerminate:], assuming you've implemented that. You're probably referring to an object that has already been released (is this ARC? The most common cause of this kind of error is failure to use ARC.)

If you haven't implemented applicationShouldTerminate:, it is possible that you've over-released the app delegate itself. NSZombies can help diagnose that.