xcode 9 crash when open storyboard

Question

XCode 9 GM Candidate 1 is currently crashing when opening a storyboard.

ProductBuildVersion: 9A235

UNCAUGHT EXCEPTION (NSInternalInconsistencyExcepti         


        

Answer 1

So I had an issue whereby as soon as I opened a storyboard in XCode 9 the file was modified (not unusual for XCode) - but then whenever I ran the app with Exception breakpoints enabled it crashed. Hitting continue from the debugger allowed the app to then run normally.

Looking at what XCode has modified in the storyboard file, it turned that at the top of the file, before the 'scenes' xml element, it was adding:

    
        GillSans
        GillSans-Light
    

Removing this stopped the weird crash issue, but modifying the storyboard keeps adding the code back in. It appears the solution would be to remove all custom fonts from the storyboard and set them in code - or hope this is just a weird bug which will be fixed in a later XCode version.