Swift: Thread 1 signal SIGABRT

Question

After upgrading Xcode from 5 to 6 beta, almost every project gives me an unexpected error after running the application. There are some other posts with this title but the error

Answer 1

Seems like there was a bug with iOS 7.1 as target.

Running tests on devices with iOS 7.1 installed now works. (17028705)

Try it again with the beta 2 update