Proving False in Object-Oriented Verification Programs by Exploiting Non-Termination

Abstract

We looked at three different object-oriented program verifiers: Gobra, KeY, and Dafny. We show that all three can be made to prove false by using a simple trick with ghost variable declaration and non-terminating code. This shows that verifiers for these languages can produce unsound results without much difficulty and that this is possibly common throughout all OO verifiers.