General Terms

Automatic techniques for helping developers in nding the root causes of software failures are extremely important in the development cycle of software. In this paper we study a dynamic modeling approach to fault localization, which is based on logic reasoning over program traces. We present a simple diagnostic performance model to assess the in uence of various parameters, such as test set size and coverage, on the debugging eort required to nd the root causes of software failures. The model shows that our approach un-ambiguously reveals the actual faults, provided that su-cient test cases are available. This optimal diagnostic per-formance is conrmed by numerical experiments. Further-more, we present preliminary experiments on the diagnostic capabilities of this approach using the single-fault Siemens benchmark set. We show that, for the Siemens set, the approach presented in this paper yields a better diagnostic ranking than other well-known techniques. Categories and Subject Descriptors D.2.5 [Software engineering]: testing and debugging