坠毁SPTrack的dealloc

Question

偶尔，我看到崩溃免受来自-dealloc在SPTrack：

Exception Type: EXC_BAD_ACCESS (SIGSEGV) 
Exception Codes: KERN_INVALID_ADDRESS at 0xb1e8ded2 
Crashed Thread: 13 

Thread 0 name: Dispatch queue: com.apple.main-thread 
Thread 0: 
0 libsystem_c.dylib    0x39bb8d5c memset$VARIANT$CortexA9 + 100 
1 CoreFoundation     0x35e1a7fc __CFAllocateObjectArray + 176 
2 CoreFoundation     0x35d62118 _CFXNotificationRemoveObservers + 420 
3 Foundation      0x33834490 -[NSNotificationCenter removeObserver:name:object:] + 228 
4 MyAppName      0x00179fd0 -[SPTrack dealloc] (SPTrack.m:291) 
5 MyAppName      0x0017993a __destroy_helper_block_141 (SPTrack.m:223) 
6 libsystem_blocks.dylib   0x352adab0 _Block_release + 220 
7 libdispatch.dylib    0x34b064b4 _dispatch_client_callout + 20 
8 libdispatch.dylib    0x34b0b1b8 _dispatch_main_queue_callback_4CF$VARIANT$mp + 220 
9 CoreFoundation     0x35de9f36 __CFRunLoopRun + 1286 
10 CoreFoundation     0x35d5ceb8 CFRunLoopRunSpecific + 352 
11 CoreFoundation     0x35d5cd44 CFRunLoopRunInMode + 100 
12 GraphicsServices    0x362992e6 GSEventRunModal + 70 
13 UIKit       0x3713b2fc UIApplicationMain + 1116 
14 MyAppName      0x0005e986 main (main.m:14) 
15 MyAppName      0x0001d8e4 start + 36 

这是在SPTrack对＃291：

[[NSNotificationCenter defaultCenter] removeObserver:self name:SPSessionDidUpdateMetadataNotification object:self.session]; 

当我把这通常发生应用程序从后台返回。

任何想法可能是什么原因？它是否试图多次删除观察者？或者self.session无效？ （使用调试器一直无法捕捉到。）

Answer 1

在CocoaLibSpotify中的cherry-picking this commit之后（按照iKenndac的建议），我不再收到这些崩溃。