How to debug and solve a crash in AFNetworking

Question

My iOS app uses AFNetworking (2.6.1), and my highest ranking crash is :

Crashed: com.apple.NSURLSession-work
EXC_BAD_ACCESS KERN_INVALID_ADDRESS 0x0004000128ab38a0

This is how most stack traces look like in Crashlytics:

Thread : Crashed: com.apple.NSURLSession-work
0  libobjc.A.dylib                0x180e29bc8 objc_msgSend + 8
1  CFNetwork                      0x181df6518 SessionConnectionLoadable::_loaderClientEvent_DidReceiveConnectionCacheKey(HTTPConnectionCacheKey*) + 56
2  CFNetwork                      0x181e75178 ___ZN19URLConnectionLoader36protocolDidReceiveConnectionCacheKeyEP22HTTPConnectionCacheKey_block_invoke + 40
3  libdispatch.dylib              0x1811fd630 _dispatch_call_block_and_release + 24
4  libdispatch.dylib              0x1811fd5f0 _dispatch_client_callout + 16
5  libdispatch.dylib              0x181209634 _dispatch_queue_drain + 864
6  libdispatch.dylib              0x1812010f4 _dispatch_queue_invoke + 464
7  libdispatch.dylib              0x18120b504 _dispatch_root_queue_drain + 728
8  libdispatch.dylib              0x18120b224 _dispatch_worker_thread3 + 112
9  libsystem_pthread.dylib        0x181411470 _pthread_wqthread + 1092
10 libsystem_pthread.dylib        0x181411020 start_wqthread + 4

I don't use kvo, and my app uses location and stays in the background at all times.

Any ideas on how to debug / recreate (I can't manage to recreate the issue in a simulator or on a device) ? Even catching the exception, without knowing where it is or how to handle it correctly would suffice in this case...

Honky

Check this link to how create an Exception breakpoint, it will point the line that is causing the crash #17803162 – Strobila

If only I could recreate it in a simulator / device - that would help, but I get these crashes via Crashlytics as they only happen "in the wild" – Honky

@UlyssesR EXC_BAD_ACCESS is not a thrown exception. An exception backtrace will never work for that kind of crash. – Neologism

Hi, having a very similar issue. github.com/AFNetworking/AFNetworking/issues/3530 is any of you using backgroundFetch and might consider that this crash is done while app NOT in foreground? Also this link might help developer.apple.com/library/ios/documentation/Cocoa/Conceptual/… – Brigandine

this issue only seems to happen on iOS 9 and not on iOS 10 – Zingg