Using Trace Data to Diagnose Non-Termination Errors

. This paper discusses black-hat and hat-nonterm, two tools for locating and diagnosing non-termination errors in Haskell programs. Both of these tools give a small trace which is intended to illuminate the cause of the non-termination error. black-hat analyses programs which contain black holes, a particularly restricted kind of non-termination error, while hatnonterm applies the approach used in black-hat to more general non-terminating programs. This paper discusses the traces generated by black-hat and hat-nonterm, as well as the approach used to generate these traces.