Attempted bug fix: QuartzCore - CA :: release_objects (X :: List <void const *> *)

Question

We got a few crashes with our application and wanted to see if any of you have the ability to gain insight or have a similar experience. I shared the crash log information below.

Launch iOS 8.1. We ran it with tools, a static analyzer, and are still trying to identify the problem.

QuartzCore CA::release_objects(X::List<void const*>*) 13 Crashed: Thread EXC_BAD_ACCESS KERN_INVALID_ADDRESS at 0x0042de0f48aa7488 Thread : Crashed: Thread 0 libobjc.A.dylib 0x0000000193debbdc objc_msgSend + 28 1 CoreFoundation 0x0000000183561228 CFRelease + 524 2 QuartzCore 0x0000000187788644 CA::release_objects(X::List<void const*>*) + 32 3 QuartzCore 0x000000018778e498 -[CAAnimation dealloc] + 80 4 libobjc.A.dylib 0x0000000193df1724 (anonymous namespace)::AutoreleasePoolPage::pop(void*) + 564 5 libobjc.A.dylib 0x0000000193df2754 (anonymous namespace)::AutoreleasePoolPage::tls_dealloc(void*) + 72 6 libsystem_pthread.dylib 0x00000001945fa3e0 _pthread_tsd_cleanup + 200 7 libsystem_pthread.dylib 0x00000001945fa0ac _pthread_exit + 140 8 libsystem_pthread.dylib 0x00000001945fb330 pthread_exit + 44 9 Foundation 0x0000000184487000 -[NSObject(NSThreadPerformAdditions) performSelectorOnMainThread:withObject:waitUntilDone:] 10 Foundation 0x0000000184555c24 __NSThread__main__ + 1096 11 libsystem_pthread.dylib 0x00000001945fbe80 _pthread_body + 164 12 libsystem_pthread.dylib 0x00000001945fbddc _pthread_body 

Answer 1

The problem is that you are doing one additional release on an object that Core Animation did not expect, so the problem occurs in your code, but appears when the animation environment completes its cleanup phase.

To solve this problem, use Profiling. Select the Allocations profiler and click the write link count in the "Configure Launch for Heap Distributions" section.

Then, when the problem hits, you can see the distribution history, and one release will not be paired and was released from one of the source code files.