Residual investigation: predictive and precise bug detection

Abstract

We introduce the concept of “residual investigation” for program analysis. A residual investigation is a dynamic check installed as a result of running a static analysis that reports a possible program error. The purpose is to observe conditions that indicate whether the statically predicted program fault is likely to be realizable and relevant. The key feature of a residual investigation is that it has to be much more precise (i.e., with fewer false warnings) than the static analysis alone, yet significantly more general (i.e., reporting more errors) than the dynamic tests in the program's test suite pertinent to the statically reported error. That is, good residual investigations encode dynamic conditions that, when taken in conjunction with the static error report, increase confidence in the existence of an error, as well as its severity, without needing to directly observe a fault resulting from the error.