cocoa - NSManagedObjectContext processPendingChanges 期间核心数据崩溃

Question

我遇到了 Core Data 崩溃(在我看来很奇怪)。据我所知，当 Core Data 进行保存并触发后续的 ManagedObjectContextDidSave 方法时，就会发生这种情况。

我很茫然，真的希望有人能帮助我或引导我走向正确的方向。

崩溃报告如下:

Exception Type:  EXC_BAD_ACCESS (SIGBUS)
Exception Codes: KERN_PROTECTION_FAILURE at 0x0000000b
Crashed Thread:  0

Thread 0 Crashed:
0   libobjc.A.dylib                 0x000026f4 objc_msgSend + 16
1   Foundation                      0x000437a4 NSClassFromObject + 8
2   Foundation                      0x0000ba54 _NSIMPForObjectAndSelector + 4
3   Foundation                      0x00095eae -[NSSortDescriptor compareObject:toObject:] + 110
4   CoreData                        0x000b0a6e +[NSFetchedResultsController(PrivateMethods) _insertIndexForObject:inArray:lowIdx:highIdx:sortDescriptors:] + 174
5   CoreData                        0x000b1496 -[NSFetchedResultsController(PrivateMethods) _postprocessInsertedObjects:] + 342
6   CoreData                        0x000b32d6 -[NSFetchedResultsController(PrivateMethods) _postprocessUpdatedObjects:] + 430
7   CoreData                        0x000b2a5e -[NSFetchedResultsController(PrivateMethods) _managedObjectContextDidChange:] + 498
8   Foundation                      0x0004bbf6 _nsnote_callback + 162
9   CoreFoundation                  0x00050af2 _CFXNotificationPostNotification + 298
10  Foundation                      0x000497f4 -[NSNotificationCenter postNotificationName:object:userInfo:] + 64
11  CoreData                        0x0002e42e -[NSManagedObjectContext(_NSInternalNotificationHandling) _postObjectsDidChangeNotificationWithUserInfo:] + 66
12  CoreData                        0x0007fd26 -[NSManagedObjectContext(_NSInternalChangeProcessing) _createAndPostChangeNotification:withDeletions:withUpdates:withRefreshes:] + 134
13  CoreData                        0x0001670a -[NSManagedObjectContext(_NSInternalChangeProcessing) _postRefreshedObjectsNotificationAndClearList] + 70
14  CoreData                        0x000164ac -[NSManagedObjectContext(_NSInternalChangeProcessing) _processRecentChanges:] + 1656
15  CoreData                        0x0004b5fa -[NSManagedObjectContext processPendingChanges] + 10
16  CoreData                        0x0003e2a4 _performRunLoopAction + 120
17  CoreFoundation                  0x0000fb50 __CFRunLoopDoObservers + 420
18  CoreFoundation                  0x00056a32 CFRunLoopRunSpecific + 1734
19  CoreFoundation                  0x00056356 CFRunLoopRunInMode + 42
20  GraphicsServices                0x00003cb8 GSEventRunModal + 108
21  GraphicsServices                0x00003d64 GSEventRun + 56
22  UIKit                           0x00002768 -[UIApplication _run] + 384
23  UIKit                           0x0000146c UIApplicationMain + 688
24  MyApp                           0x000022d2 main (main.m:14)
25  MyApp                           0x00002248 start + 44

Answer 1

看起来数据库数组之一中的一项被释放了太多次(因此被释放)。尝试对数组进行排序、与已释放的对象进行比较时会崩溃。

尝试使用 NSZombieEnabled 运行您的程序-- 它可以防止释放，因此您可以看到哪个对象正在接收发送给它的保留计数为 0 的消息。