ios - Making com.apple.CoreData.ConcurrencyDebug 1 work

Question

I am trying to migrate some code to use an NSManagedObjectContext with NSPrivateQueueConcurrencyType.

I'm sometimes getting very odd errors after saving the context to its parent, and then saving the parent. I'm wondering if these are due to be not using the NSPrivateQueueConcurrencyType context correctly.

I've turned on -com.apple.CoreData.ConcurrencyDebug 1 to try to debug this. I'm pretty sure that this is not working however. If I perform operations on managed object context or change its objects without using performBlock:, I don't get an error or a throw.

Here's how I've set up the scheme's arguments:. I've also tried it without the leading -.

Any idea what I'm doing wrong?

Answer 1

The argument -com.apple.CoreData.ConcurrencyDebug is available from iOS > 8 and OSX > 10.10 : make sure you target the right platform.

The console should log this if the flag is enabled :

CoreData: annotation: Core Data multi-threading assertions enabled.

Source : Core Data Concurrency Debugging from Ole Begemann