Hi all, We recently got some new weird crash reports on our monitoring systems. These crashes happen in the table view diffable data source on iOS 17. We had these crashes never before on any other operating systems. The error says: Diffable data source detected an item identifier whose hash value changed. The hash value of an identifier cannot change once it has been added to a snapshot. Based on this information, an item's hash value should never change while we expect diffable datasource's apply() function to reload a row if its hash value changed. Full report of bug attached c5671824114048ed87d18f5afe967a97-symbolicated.crash

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!