Coincidental correctness: An interference or interface to successful fault localization?

In software debugging, statistical fault localization techniques contrast dynamic spectra of program elements to estimate the location of faults in faulty programs. Coincidental correctness may have a negative impact on these techniques because faults can also be triggered in an observed non-failed run and thus disturbs the assessment of fault locations. However, eliminating the confounding relies on the accuracy of recognizing them. This paper makes use of the presence of coincidental correctness as an effective interface to the success of fault localization. We calculate the distribution overlapping of dynamic spectrum in failed runs and in non-failed runs to find out the fault-leading predicates, and further reduce the region by referencing the inter-class distances of the spectra to suppress the less suspicious candidates. Empirical results show that our technique can outperform representative existing predicate-based fault localization techniques.