Interactive Analysis in FLUCTUAT

Static analyzers have the invaluable advantage to produce analysis results fully automatically. However, when based on abstract interpretation, they often require fine parameters tuning to succeed on local technical parts in large programs. In such cases, an interactive mode could be appreciable to define some analysis parameters on-the-fly e.g. loop unrolling, partitioning -, but also to identify data that produce a specific warning. We have implemented an interactive analysis in the FLUCTUAT tool analysis tool of numerical C and Ada programs that delivers bounds both for the domains and for the error due to finite precision computation. The analysis in this mode is interruptible and it authorizes on-the-fly definitions of assertions. The analysis is especially interesting to refine the diagnosis of an alarm, either towards a false alarm or a counter-example.