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Verified Software Units for Simple DFA Modules and Objects in C

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Leveraging Applications of Formal Methods, Verification and Validation. Software Engineering (ISoLA 2022)

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Finite state machines occur ubiquitously in modern software, often in the form of C code that is synthesized from higher-level descriptions. To explore how the resulting code bases can be integrated into foundational verification infrastructures, we present formal specifications and machine-checked proofs of DFA representations using VST, a higher-order separation logic for C implemented in the Coq proof assistant. Paying particular attention to modularity and API-level representation hiding, we consider statically linked modules as well as object-inspired programming styles. Exploiting the abstraction capabilities of a recent VST enhancement, Verified Software Units (VSU), we complement separate compilation by separate verification and obtain instances of behavioral subtyping as separation logic entailments between suitable object representation predicates.

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Funding Information. This material is based on work supported by the Defense Advanced Research Projects Agency (DARPA), Contract No. HR001120C0160. Additional support was provided by the National Science Foundation under the award 1005849, Verified High Performance Data Structure Implementations.

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Correspondence to Lennart Beringer .

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Beringer, L. (2022). Verified Software Units for Simple DFA Modules and Objects in C. In: Margaria, T., Steffen, B. (eds) Leveraging Applications of Formal Methods, Verification and Validation. Software Engineering. ISoLA 2022. Lecture Notes in Computer Science, vol 13702. Springer, Cham.

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