保存核心数据的managedobjectcontext时，我的应用程序崩溃了。
崩溃日志如下：
Code Type: X86-64 (Native)
Parent Process: launchd [182]
Responsible: Neat [9540]
User ID: 835384806
Date/Time: 2014-10-15 18:55:11.890 +0530
OS Version: Mac OS X 10.9.4 (13E28)
Report Version: 11
Anonymous UUID: B7542E2A-7E0A-9BF4-4026-642BC0899AEA
Sleep/Wake UUID: D3DA262A-ADFC-4D46-8793-1153578CC1D2
Crashed Thread: 0 Dispatch queue: com.apple.main-thread
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: EXC_I386_GPFLT
Application Specific Information:
objc_msgSend() selector name: release
Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0 libobjc.A.dylib 0x00007fff87619097 objc_msgSend + 23
1 com.apple.CoreData 0x00007fff8ad8f797 -[_PFManagedObjectReferenceQueue _processReferenceQueue:] + 1575
2 com.apple.CoreData 0x00007fff8ad969f7 -[NSManagedObjectContext(_NSInternalChangeProcessing) _processRecentChanges:] + 3575
3 com.apple.CoreData 0x00007fff8ad6e5c4 _performRunLoopAction + 372
4 com.apple.CoreFoundation 0x00007fff838a4d67 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 23
5 com.apple.CoreFoundation 0x00007fff838a4cd7 __CFRunLoopDoObservers + 391
6 com.apple.CoreFoundation 0x00007fff83895e94 CFRunLoopRunSpecific + 340
7 com.apple.HIToolbox 0x00007fff8501aa0d RunCurrentEventLoopInMode + 226
8 com.apple.HIToolbox 0x00007fff8501a685 ReceiveNextEventCommon + 173
9 com.apple.HIToolbox 0x00007fff8501a5bc _BlockUntilNextEventMatchingListInModeWithFilter + 65
10 com.apple.AppKit 0x00007fff8a1f224e _DPSNextEvent + 1434
11 com.apple.AppKit 0x00007fff8a1f189b -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] + 122
12 com.apple.AppKit 0x00007fff8a1e599c -[NSApplication run] + 553
13 com.apple.AppKit 0x00007fff8a1d0783 NSApplicationMain + 940
14 com.neatreceipts.nrm 0x000000010edd6cc4 0x10edd5000 + 7364
任何人都可以告诉我可能是我的问题，我该如何解决这个问题。