100+ “Class implemented in both MapKit and VectorKit” warnings with Xcode 9.0.1 and above

Question

While running my project (which doesn\'t even use MapKit), my console gets spammed with more than a hundred class duplicate warnings:

objc[63

Answer 1

Resetting the iOS simulator fixed this for me. Simulator -> Hardware -> Erase All Content and Settings...

Answer 2

As you can see, there's something wrong with CoreSimulator of /Applications/Xcode.app. Apple Xcode Developer defined this symbol in both MapKit and VectorKit, which is the fundamental error.

You cannot modify Xcode, so only Apple's Staff can solve it.

Just stop wasting your time, except falling back to Xcode 9.0