An Empirical Study on Higher-Order Mutation-Based Fault Localization

Abstract

Fault localization is one of the most expensive activities in software debugging. Mutation-based fault localization (MBFL) is a commonly studied technique that applied mutation analysis to find the location of faults in the programs. Previous studies showed that MBFL adopted First-Order-Mutants (FOMs) that could achieve promising results in single-fault localization, but it did not perform well in multiple-fault localization. Recently, Higher-Order-Mutants (HOMs) were proposed for modeling complex faults but whether HOMs can help in fault localization is still unknown. In this paper, we investigate the performance of MBFL with FOMs and HOMs on single- and multiple-fault localization. Moreover, to study the characteristics of HOMs, we divide HOMs into three groups (i.e. Accurate HOMs, Partially accurate HOMs, and Inaccurate HOMs) by considering different mutation locations. Based on the empirical results on 186 versions of six real-world programs, we find that (1) In single-fault localization, FOMs can achieve better performance than HOMs. (2) However, in multiple-fault localization, HOMs (2-HOMs) localize more faults than FOMs. (3) Furthermore, different types of HOMs have different fault localization effectiveness, where Accurate HOMs outperform the other two HOMs categories. Therefore, the researchers should propose methods to find HOMs more useful for fault localization.