Duplicate symbol error when adding NSManagedObject subclass, duplicate link

Question

I was trying to create NSManagedObject subclasses (2 related entities) automatically in Xcode. They are generated like this:

Answer 1

I recently tried the above answer and it failed. Somehow, Xcode was still generating the files.

I solved it using the following method:

• Mark all entities as Abstract
• Build
• Remove Abstract flag
• Build
• Success !

This sounds like a bug in Xcode...