Enhancing Compositional Static Analysis with Dynamic Analysis

In this paper we introduce a novel method for improving static analysis of real code by using dynamic analysis. We have implemented our technique to enhance the Infer static analyzer [6] for Erlang by supplementing its analysis with data obtained by FAUSTA [24] dynamic analysis. We present the technical details of the algorithm combining static and dynamic analysis and a case study on its evaluation on WhatsApp's Erlang code to detect software defects. Results show an increase in detected bugs in 76% of the runs when data from dynamic analysis is used. In particular, on average, data provided by dynamic analysis for 1 function enables static analysis of 2.1 additional functions. Moreover, dynamic data enabled analysis of a property not verifiable using static analysis alone.