debugging with control-flow breakpoints
Modern source-level debuggers support dynamic breakpoints that are guarded by conditions based on program state. Such breakpoints address situations where a static breakpoint is not sufficiently precise to characterise a point of interest in program execution. However, we believe that current IDE support for dynamic breakpoints are cumbersome to use. Firstly, guard conditions formulated in (non-aspect-oriented) source-languages cannot directly express control-flow conditions, forcing developers to seek alternative formulations. Secondly, guard-conditions can be complex expressions and manually typing them is cumbersome.We present the Control-flow Breakpoint Debugger ( CBD ). CBD uses a dynamic pointcut language to characterise control-flow breakpoints---dynamic breakpoints which are conditional on the control-flow through which they were reached. CBD provides a "point-and-click" GUI to specify and incrementally refine control-flow breakpoints, thereby avoiding the burden of manually editing the potentially complex expressions that define them.We performed 20 case studies debugging and fixing documented bugs in 3 existing applications. Our results show that dynamic breakpoints in general are useful in practice, and that CBD's GUI allows specifying them adequately in the majority of cases.
pointcut language case studies debugger interface