Same thing. Seems to be Xcode/SDK version related. Random Core Data related crashes starts to occur when App is compiled using Xcode 12.0-12.2 beta.
When app is compiled using Xcode 11.5 or older, app doesn't crash anymore. Runs fine also on IOS 14. Using older Xcode 11 is the current workaround.
And yeah, there are errors when app is executed with -com.apple.CoreData.ConcurrencyDebug 1 on all XCode versions. But those has been in project for ages.
It seems that something has changed on new Xcode/SDK, which makes builds more prone crashing on Core Data coding errors. Either it's not having anymore compile time magic which fixes the coding errors, or something is changed on execution/ dispatching of Core Data operations..
Topic:
App & System Services
SubTopic:
Core OS
Tags: