CGA Call Graph Analyzer - Locating and Understanding Functionality within the Gnu Compiler Collection's Million Lines of Code

In this paper we describe the application of our tool (CGA) for locating and understanding functionality in unfamiliar code of complex software systems onto the Gnu compiler collection GCC (approx. 1 million lines of C-code). The analysis' goal is to identify and understand those code locations that implement GCC's functionality of 'parsing constructors in C++ programs'.