Core Data exception with reason "Can't get value for 'batch' in bindings"

We're seeing a crash that is only reproducible on a device with iOS 14+ when running our app built using Xcode 12.0.1 (latest iOS 14 SDKs). The exception is thrown when doing a fetch request for a managed object from our Core Data store. Below is the call stack from the exception. I thought we might be resetting the context while this request was being made, but we're not. Has anyone else been seeing this or have an idea on the cause?

Code Block
* Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Can't get value for 'batch' in bindings {
}.'
* First throw call stack:
(
0 CoreFoundation 0x00007fff2043a126 exceptionPreprocess + 242
1 libobjc.A.dylib 0x00007fff20177f78 objc_exception_throw + 48
2 Foundation 0x00007fff2088bedc -[NSVariableExpression _expressionWithSubstitutionVariables:] + 0
3 Foundation 0x00007fff2075ac7b -[NSComparisonPredicate evaluateWithObject:substitutionVariables:] + 264
4 CoreData 0x00007fff2511ec68 -[NSDictionaryStoreMap handleFetchRequest:] + 481
5 CoreData 0x00007fff2511dfd2 -[NSMappedObjectStore executeFetchRequest:withContext:] + 230
6 CoreData 0x00007fff251e10a2 65-[NSPersistentStoreCoordinator executeRequest:withContext:error:]_block_invoke.797 + 3219
7 CoreData 0x00007fff251d988d 55-[NSPersistentStoreCoordinator _routeHeavyweightBlock:]_block_invoke + 55
8 CoreData 0x00007fff251edf0a gutsOfBlockToNSPersistentStoreCoordinatorPerform + 182
9 libdispatch.dylib 0x000000010a6b0a88 _dispatch_client_callout + 8
10 libdispatch.dylib 0x000000010a6bfcac _dispatch_lane_barrier_sync_invoke_and_complete + 132
11 CoreData 0x00007fff251d9492 _perform + 169
12 CoreData 0x00007fff251d9740 -[NSPersistentStoreCoordinator _routeHeavyweightBlock:] + 172
13 CoreData 0x00007fff250d640e -[NSPersistentStoreCoordinator executeRequest:withContext:error:] + 1684
14 CoreData 0x00007fff250d49c2 -[NSManagedObjectContext executeFetchRequest:error:] + 885
15 CoreData 0x00007fff251a9d7f -[NSManagedObjectContext _parentObjectsForFetchRequest:inContext:error:] + 477
16 CoreData 0x00007fff251aa774 82-[NSManagedObjectContext(_NestedContextSupport) executeRequest:withContext:error:]_block_invoke + 603
17 CoreData 0x00007fff25109de8 internalBlockToNSManagedObjectContextPerform + 89
18 libdispatch.dylib 0x000000010a6b0a88 _dispatch_client_callout + 8
19 libdispatch.dylib 0x000000010a6bfcac _dispatch_lane_barrier_sync_invoke_and_complete + 132
20 CoreData 0x00007fff25109d6f _perform + 196
21 CoreData 0x00007fff25109b93 -[NSManagedObjectContext(_NestedContextSupport) executeRequest:withContext:error:] + 175
22 CoreData 0x00007fff250d49c2 -[NSManagedObjectContext executeFetchRequest:error:] + 885
23 CoreData 0x00007fff251a9d7f -[NSManagedObjectContext _parentObjectsForFetchRequest:inContext:error:] + 477
24 CoreData 0x00007fff251aa774 82-[NSManagedObjectContext(_NestedContextSupport) executeRequest:withContext:error:]_block_invoke + 603
25 CoreData 0x00007fff25109de8 internalBlockToNSManagedObjectContextPerform + 89
26 libdispatch.dylib 0x000000010a6b0a88 _dispatch_client_callout + 8
27 libdispatch.dylib 0x000000010a6bfe11 _dispatch_async_and_wait_invoke + 175
28 libdispatch.dylib 0x000000010a6b0a88 _dispatch_client_callout + 8
29 libdispatch.dylib 0x000000010a6bef23 _dispatch_main_queue_callback_4CF + 1152
30 CoreFoundation 0x00007fff203a8276 CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE + 9
31 CoreFoundation 0x00007fff203a2b06 CFRunLoopRun + 2685
32 CoreFoundation 0x00007fff203a1b9e CFRunLoopRunSpecific + 567
33 GraphicsServices 0x00007fff2b773db3 GSEventRunModal + 139
34 UIKitCore 0x00007fff24660af3 -[UIApplication _run] + 912
35 UIKitCore 0x00007fff24665a04 UIApplicationMain + 101
36 XXXX 0x0000000106de2d69 main + 153
37 libdyld.dylib 0x00007fff20257415 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Can't get value for 'batch' in bindings {
}.'







Answered by Sachin.gupta in 639734022
I am also facing the same issue with XCode12 + iOS14, a quick fix is remove batch size (request.fetchBatchSize = 0) will fix this issue but this will impact performance of the app.

if I create build using Xcode 11.5 and run in iOS 14 app works fine without any issues but when use XCode12 getting this issue
Accepted Answer
I am also facing the same issue with XCode12 + iOS14, a quick fix is remove batch size (request.fetchBatchSize = 0) will fix this issue but this will impact performance of the app.

if I create build using Xcode 11.5 and run in iOS 14 app works fine without any issues but when use XCode12 getting this issue
Thanks Sachin! That works for me too. Hopefully Apple will have a fix in the next Xcode/SDKs release.
Core Data exception with reason "Can't get value for 'batch' in bindings"
 
 
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