Hi everyone,
I'm experiencing crashes that consistently occur on iOS 18 devices, which seem to share a common root cause. I'm hoping for some guidance. Here are the details of the crashes as received from Xcode Organizer:
Crash Trace 1:
0 CoreFoundation 0x0000000192c50e54 CF_IS_OBJC + 76 (CFRuntime.c:461)
1 CoreFoundation 0x0000000192c4dd3c CFRelease + 60 (CFRuntime.c:1202)
2 CoreFoundation 0x0000000192d015e0 _signalEventSync + 252 (CFStream.c:636)
3 CoreFoundation 0x0000000192d53050 ___signalEventQueue_block_invoke + 28 (CFStream.c:646)
4 libdispatch.dylib 0x000000019a93c370 _dispatch_call_block_and_release + 32 (init.c:1549)
5 libdispatch.dylib 0x000000019a93e0d0 _dispatch_client_callout + 20 (object.m:576)
6 libdispatch.dylib 0x000000019a9456d8 _dispatch_lane_serial_drain + 744 (queue.c:3934)
7 libdispatch.dylib 0x000000019a9461e0 _dispatch_lane_invoke + 380 (queue.c:4025)
8 libdispatch.dylib 0x000000019a951258 _dispatch_root_queue_drain_deferred_wlh + 288 (queue.c:7193)
9 libdispatch.dylib 0x000000019a950aa4 _dispatch_workloop_worker_thread + 540 (queue.c:6787)
10 libsystem_pthread.dylib 0x000000021a00fc7c _pthread_wqthread + 288 (pthread.c:2696)
11 libsystem_pthread.dylib 0x000000021a00c488 start_wqthread + 8 (:-1)
Crash Trace 2:
0 libobjc.A.dylib 0x0000000186f33c20 objc_msgSend + 32
1 CoreFoundation 0x0000000189cb14b8 _inputStreamCallbackFunc + 36 (CFObject.m:1952)
2 CoreFoundation 0x0000000189cb0aa8 _signalEventSync + 216 (CFStream.c:626)
3 CoreFoundation 0x0000000189d01e30 ___signalEventQueue_block_invoke + 28 (CFStream.c:646)
4 libdispatch.dylib 0x0000000191948370 _dispatch_call_block_and_release + 32 (init.c:1549)
5 libdispatch.dylib 0x000000019194a0d0 _dispatch_client_callout + 20 (object.m:576)
6 libdispatch.dylib 0x00000001919516d8 _dispatch_lane_serial_drain + 744 (queue.c:3934)
7 libdispatch.dylib 0x00000001919521e0 _dispatch_lane_invoke + 380 (queue.c:4025)
8 libdispatch.dylib 0x000000019195d258 _dispatch_root_queue_drain_deferred_wlh + 288 (queue.c:7193)
9 libdispatch.dylib 0x000000019195caa4 _dispatch_workloop_worker_thread + 540 (queue.c:6787)
10 libsystem_pthread.dylib 0x000000021214bc7c _pthread_wqthread + 288 (pthread.c:2696)
11 libsystem_pthread.dylib 0x0000000212148488 start_wqthread + 8
Crash Trace 3:
0 libobjc.A.dylib 0x00000001941d9ce8 objc_loadWeakRetained + 156 (NSObject.mm:525)
1 CoreFoundation 0x0000000196d0a0f4 _outputStreamCallbackFunc + 36 (CFObject.m:1960)
2 CoreFoundation 0x0000000196d09724 _signalEventSync + 216 (CFStream.c:626)
3 CoreFoundation 0x0000000196d07948 ___signalEventQueue_block_invoke + 28 (CFStream.c:646)
4 libdispatch.dylib 0x000000019e9de248 _dispatch_call_block_and_release + 32 (init.c:1549)
5 libdispatch.dylib 0x000000019e9dffa8 _dispatch_client_callout + 20 (object.m:576)
6 libdispatch.dylib 0x000000019e9e75cc _dispatch_lane_serial_drain + 768 (queue.c:3934)
7 libdispatch.dylib 0x000000019e9e8124 _dispatch_lane_invoke + 380 (queue.c:4025)
8 libdispatch.dylib 0x000000019e9f338c _dispatch_root_queue_drain_deferred_wlh + 288 (queue.c:7193)
9 libdispatch.dylib 0x000000019e9f2bd8 _dispatch_workloop_worker_thread + 540 (queue.c:6787)
10 libsystem_pthread.dylib 0x00000002220f3680 _pthread_wqthread + 288 (pthread.c:2696)
11 libsystem_pthread.dylib 0x00000002220f1474 start_wqthread + 8
Notable Points:
- All crashes occur only on iOS 18 and newer versions.
- The crashes are independent of the Xcode version used to build the app (tested with both Xcode 15.4 and 16).
- All crash traces occur in CoreFoundation and seem to have nothing related to our app codebase.
- I've attempted to profile the app using Instruments to identify any zombie objects, but the crashes do not manifest on my own devices.
- I've referred to discussions, including this forum thread, but have not yet found a solution.
Questions:
- Has anyone else encountered similar issues on iOS 18?
- Are there specific aspects of iOS 18 that might contribute to these CoreFoundation and libobjc-related crashes?
- Would appreciate any suggestions for further diagnostics or potential workarounds.
Thank you for your help!