Definition of software fault emulation operators: a field data study

Abstract

This paper proposes a set of operators for software fault emulation through low-level code mutations. The definition of these operators was based on the analysis of an extensive collection of real software faults. Using the Orthogonal Defect Classification as a starting point, faults were classified in a detailed manner according to the high-level constructs where the faults reside and their effects in the program. We observed that a large percentage of faults fall in well-defined classes and can be characterized in a very precise way, allowing accurate emulation through a small set of mutation operators. The resulting operators closely emulate a broad range of common programmer mistakes. Furthermore, as the mutation is performed directly at the executable code, software faults can be injected in targets for which source code is not available.