TBCppA: A Tracer Approach for Automatic Accurate Analysis of C Preprocessor´s Behaviors

C preprocessor (CPP) is a major cause that makes it much difficult to accurately analyze C source code, which is indispensable to refactoring tools for C programs. To accurately analyze C source code, we need to generate CPP mapping information between unpreprocessed C sourcecode and preprocessed one. Previous works generate CPP mapping information by extending the existing CPP, which results in low portability and low maintainability due to the strong dependency of CPP implementation. To solve this problem, this paper proposes a novel approach (called TBCppA) based on tracer, which generates CPP mapping information by instrumenting the unpreprocessed C source code using XML-like tags called "tracers". The advantage of TBCppA is high portability and high maintainability, which the previous methods do not have. We successfully implemented a first prototype of TBCppA, and our preliminary evaluation of applying TBCppA to gcc-4.1.1 produced promising results.