Object Model Construction for Inheritance in C++ and Its Applications to Program Analysis
Jing Yang and Gogul Balakrishnan and Naoto Maeda and Franjo Ivancic and Aarti Gupta and Nishant Sinha and Sriram Sankaranarayanan and Naveen Sharma
Modern object-oriented programming languages such as C++ provide convenient abstractions and data encapsulation mechanisms for software developers. However, these features also complicate testing and static analysis of programs that utilize object-oriented programming concepts. In particular, the C++ language exhibits features such as multiple inheritance, static and dynamic typecasting that make static analyzers for C++ quite hard to implement. In this paper, we present an approach where static analysis is performed by lowering the original C++ program into a semantically equivalent C program. However, unlike existing translation mechanisms that utilize complex pointer arithmetic operations, virtual-base offsets, virtual-function pointer tables, and calls to run-time libraries to model C++ features, our translation is targeted towards making static program analyzers for C++ easier to write and provide more precise results. We have implemented our ideas in a framework for C++ called CILpp that is analogous to the popular C Intermediate Language (CIL) framework. We evaluate the effectiveness of our translation in a bug finding tool that uses abstract interpretation and model checking. The bug finding tool uncovered several previously unknown bugs in C++ open source projects.