CRII: SHF: General, Precise and Accurate Fault Localization

Locating faults is one of the (if not the) most expensive tasks in software development. Given the complexity of software systems, identifying a fault is like searching for a needle in a haystack. This project explores a general approach that will aid programmers in locating faults in software systems. The goal is to develop a methodology for pinpointing at the exact fault locations in a program, based on evidences collected from program executions. This project can greatly reduce software development cost. More broadly, this project can advance the scientific knowledge of fault localization in general. Advances that aid programmer in debugging will also make computer science education more accessible to the public. The project explores novel techniques for general, precise and accurate fault localization. The new method is applicable to various representations of program execution with different granularities, using a novel execution trace model. Based on probabilistic inference, it accurately pinpoints at the most likely fault locations in a program, rather than reporting every location that might contribute to a failure, or reporting a code fragment that is highly correlated with failures. The practicality of this approach will be demonstrated on complex real-world systems.