WG211/M9Kaestner

Christian Kaestner

Despite much research on sophisticated programming languages and generators to implement software product lines, practitioners still implement variability in most industrial product lines with the C preprocessor. The ad-hoc nature and undisciplined use of file inclusion, macro substitution and conditional compilation on text level makes analysis difficult. While product-line-aware type systems and safe generators have been developed for novel languages, product lines implemented with the C preprocessor must still be checked by checking the (potentially millions of) generated variants instead of checking the generator. We present an approach to parse, analyze, and type check unpreprocessed C code including all #ifdef variability. To that end, we are developing a partial preprocessor, a specialized feature-aware parser, and a product-line-aware type system for C. Our long term goal is to type check all variants of the Linux kernel with its over 8000 features.