CoreData/CloudKit 0xdead10cc

Question

I’m getting a 0xdead10cc crash in a basic CoreData/CloudKit application. I only have one CoreData save call and it's made when the app is in the foreground and it's minor so I don't think it's being caused by that. My best guess is that it's related to background syncing of CloudKit. Does anyone know how to fix it? I've been advised that adding the following code around any saves will fix it, but it seems weird that this is the solution. I would expect the inner CoreData/CloudKit engine to handle this.

ProcessInfo().performActivity(reason: "Persisting to context") {
    // Save to context here
}

Here is the crashing thread

Thread 7:
0   libsystem_kernel.dylib          0x00000001edc086f4 guarded_pwrite_np + 8 (:-1)
1   libsqlite3.dylib                0x00000001ca71b6e4 seekAndWrite + 456 (sqlite3.c:44287)
2   libsqlite3.dylib                0x00000001ca6d5df4 unixWrite + 180 (sqlite3.c:44365)
3   libsqlite3.dylib                0x00000001ca723b90 pagerWalFrames + 872 (sqlite3.c:67093)
4   libsqlite3.dylib                0x00000001ca6d5b14 sqlite3PagerCommitPhaseOne + 316 (sqlite3.c:70409)
5   libsqlite3.dylib                0x00000001ca6c6494 sqlite3BtreeCommitPhaseOne + 172 (sqlite3.c:81106)
6   libsqlite3.dylib                0x00000001ca6c605c vdbeCommit + 1136 (sqlite3.c:94124)
7   libsqlite3.dylib                0x00000001ca69f778 sqlite3VdbeHalt + 1340 (sqlite3.c:94534)
8   libsqlite3.dylib                0x00000001ca6c0618 sqlite3VdbeExec + 42648 (sqlite3.c:103922)
9   libsqlite3.dylib                0x00000001ca6b56c0 sqlite3_step + 960 (sqlite3.c:97886)
10  CoreData                        0x00000001a459ab38 _execute + 128 (NSSQLiteConnection.m:4614)
11  CoreData                        0x00000001a45fe004 -[NSSQLiteConnection commitTransaction] + 728 (NSSQLiteConnection.m:3278)
12  CoreData                        0x00000001a469888c _executeGenerateObjectIDRequest + 388 (NSSQLCore_Functions.m:6021)
13  CoreData                        0x00000001a46986a4 -[NSSQLGenerateObjectIDRequestContext executeRequestCore:] + 28 (NSSQLObjectIDRequestContext.m:42)
14  CoreData                        0x00000001a45fb380 -[NSSQLStoreRequestContext executeRequestUsingConnection:] + 240 (NSSQLStoreRequestContext.m:183)
15  CoreData                        0x00000001a45fb0a8 __52-[NSSQLDefaultConnectionManager handleStoreRequest:]_block_invoke + 60 (NSSQLConnectionManager.m:307)
16  CoreData                        0x00000001a45fafe0 __37-[NSSQLiteConnection performAndWait:]_block_invoke + 48 (NSSQLiteConnection.m:755)
17  libdispatch.dylib               0x00000001a4357fa8 _dispatch_client_callout + 20 (object.m:576)
18  libdispatch.dylib               0x00000001a43677fc _dispatch_lane_barrier_sync_invoke_and_complete + 56 (queue.c:1104)
19  CoreData                        0x00000001a45b5ba4 -[NSSQLiteConnection performAndWait:] + 176 (NSSQLiteConnection.m:752)
20  CoreData                        0x00000001a45b5a68 -[NSSQLDefaultConnectionManager handleStoreRequest:] + 248 (NSSQLConnectionManager.m:302)
21  CoreData                        0x00000001a45b5938 -[NSSQLCoreDispatchManager routeStoreRequest:] + 228 (NSSQLCoreDispatchManager.m:60)
22  CoreData                        0x00000001a45b573c -[NSSQLCore dispatchRequest:withRetries:] + 172 (NSSQLCore.m:4044)
23  CoreData                        0x00000001a46737b4 -[NSSQLCore _obtainPermanentIDsForObjects:withNotification:error:] + 1324 (NSSQLCore.m:2830)
24  CoreData                        0x00000001a460ba98 -[NSSQLCore _prepareForExecuteRequest:withContext:error:] + 272 (NSSQLCore.m:2946)
25  CoreData                        0x00000001a460a0f8 __65-[NSPersistentStoreCoordinator executeRequest:withContext:error:]_block_invoke.547 + 8988 (NSPersistentStoreCoordinator.m:2995)
26  CoreData                        0x00000001a45d6660 -[NSPersistentStoreCoordinator _routeHeavyweightBlock:] + 264 (NSPersistentStoreCoordinator.m:668)
27  CoreData                        0x00000001a45ded28 -[NSPersistentStoreCoordinator executeRequest:withContext:error:] + 1200 (NSPersistentStoreCoordinator.m:2810)
28  CoreData                        0x00000001a4655988 -[NSManagedObjectContext save:] + 984 (NSManagedObjectContext.m:1593)
29  CoreData                        0x00000001a46f47dc __52+[NSCKEvent beginEventForRequest:withMonitor:error:]_block_invoke_2 + 352 (NSCKEvent.m:76)
30  CoreData                        0x00000001a45c28f0 developerSubmittedBlockToNSManagedObjectContextPerform + 476 (NSManagedObjectContext.m:3984)
31  libdispatch.dylib               0x00000001a4357fa8 _dispatch_client_callout + 20 (object.m:576)
32  libdispatch.dylib               0x00000001a43677fc _dispatch_lane_barrier_sync_invoke_and_complete + 56 (queue.c:1104)
33  CoreData                        0x00000001a4615c34 -[NSManagedObjectContext performBlockAndWait:] + 308 (NSManagedObjectContext.m:4108)
34  CoreData                        0x00000001a46f45ac __52+[NSCKEvent beginEventForRequest:withMonitor:error:]_block_invoke + 192 (NSCKEvent.m:66)
35  CoreData                        0x00000001a4825e68 -[PFCloudKitStoreMonitor performBlock:] + 92 (PFCloudKitStoreMonitor.m:148)
36  CoreData                        0x00000001a46f4394 +[NSCKEvent beginEventForRequest:withMonitor:error:] + 256 (NSCKEvent.m:61)
37  CoreData                        0x00000001a47cc6ec __57-[NSCloudKitMirroringDelegate _performExportWithRequest:]_block_invoke + 260 (NSCloudKitMirroringDelegate.m:1433)
38  CoreData                        0x00000001a47c9970 __92-[NSCloudKitMirroringDelegate _openTransactionWithLabel:assertionLabel:andExecuteWorkBlock:]_block_invoke + 72 (NSCloudKitMirroringDelegate.m:957)
39  libdispatch.dylib               0x00000001a4356248 _dispatch_call_block_and_release + 32 (init.c:1549)
40  libdispatch.dylib               0x00000001a4357fa8 _dispatch_client_callout + 20 (object.m:576)
41  libdispatch.dylib               0x00000001a435f5cc _dispatch_lane_serial_drain + 768 (queue.c:3934)
42  libdispatch.dylib               0x00000001a4360158 _dispatch_lane_invoke + 432 (queue.c:4025)
43  libdispatch.dylib               0x00000001a436b38c _dispatch_root_queue_drain_deferred_wlh + 288 (queue.c:7193)
44  libdispatch.dylib               0x00000001a436abd8 _dispatch_workloop_worker_thread + 540 (queue.c:6787)
45  libsystem_pthread.dylib         0x0000000227213680 _pthread_wqthread + 288 (pthread.c:2696)
46  libsystem_pthread.dylib         0x0000000227211474 start_wqthread + 8 (:-1)