Search arXivSearch

arXiv · 2501.12313

Correctness Witnesses with Function Contracts

Abstract

Software verification witnesses are a common exchange format for software verification tools. They were developed to provide arguments supporting the verification result, allowing other tools to reproduce the verification results. Correctness witnesses in the current format (version 2.0) allow only for the encoding of loop and location invariants using C expressions. This limits the correctness arguments that verifiers can express in the witness format. One particular limitation is the inability to express function contracts, which consist of a pre-condition and a post-condition for a function. We propose an extension to the existing witness format 2.0 to allow for the specification of function contracts. Our extension includes support for several features inspired by ACSL (\result, \old, \at). This allows for the export of more information from tools and for the exchange of information with tools that require function contracts.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Matthias Heizmann, Dominik Klumpp, Marian Lingsch-Rosenfeld, Frank Schüssele. 2025-01-21. Correctness Witnesses with Function Contracts. https://arxiv.org/abs/2501.12313

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Sound State Encodings in Translational Separation Logic Verifiers (Extended Version)

Automated program verifiers are often organized into a front-end, which encodes an input program into an intermediate verification language (IVL), and a back-end, which proves that the IVL program is correct. Soundness of such translational verifiers requires that the back-end verification is sound and that correctness of the IVL program implies correctness of the input program. Existing formalizations for translational verifiers based on separation logic target the former, but support the latter only under the strong assumption that there exists a separation logic for the input program with the same state model as the IVL. This assumption is unrealistic in practice, especially since the state model also defines the supported separation logic resources. We present the first formal framework for proving the soundness of translational separation logic verifiers with non-trivial state encodings. To be applicable to various front-ends and IVLs, our framework only assumes the existence of a homomorphic encoding relation between the front-end and IVL state models. At the core of our framework is a novel condition, backward satisfiability, which is crucial to guarantee the soundness of the front-end translation. We formalize our framework for front-end verifiers based on concurrent separation logic and separation logic IVLs, such as Raven, VeriFast, and Viper. We demonstrate its expressiveness by proving soundness for three common state encodings. Our framework and all proofs are formalized in Isabelle/HOL.

cs.PL

A Deductive Verification Infrastructure for Probabilistic Programs (Extended Version)

This paper presents a quantitative program verification infrastructure for discrete probabilistic programs. Our infrastructure can be viewed as the probabilistic analogue of Boogie: its central components are an intermediate verification language (IVL) together with a real-valued logic. Our IVL provides a programming-language-style for expressing verification conditions whose validity implies the correctness of a program under investigation. As our focus is on verifying quantitative properties such as bounds on expected outcomes, expected run-times, or termination probabilities, off-the-shelf IVLs based on Boolean first-order logic do not suffice. Instead, a paradigm shift from the standard Boolean to a real-valued domain is required. Our IVL features quantitative generalizations of standard verification constructs such as assume- and assert-statements. Verification conditions are generated by a weakest-precondition-style semantics, based on our real-valued logic. We show that our verification infrastructure supports natural encodings of numerous verification techniques from the literature. With our SMT-based implementation, we automatically verify a variety of benchmarks. To the best of our knowledge, this establishes the first deductive verification infrastructure for expectation-based reasoning about probabilistic programs.

cs.PL

On the computational complexity of JavaScript regex matching

Despite widespread use, the complexity of the matching problem for modern regular expressions languages remains unclear. Previous work proved that an idealized regular expression language with backreferences and lookarounds had PSPACE-complete matching. We extend this work to a real-world regex language by proving that JavaScript regex matching with expanded lower-bounded quantifiers is PSPACE-complete. We then generalize the result: we show that PSPACE-hardness survives the removal of negative lookarounds, and that removing all lookarounds leads to an OptP-complete parsing problem. Our core arguments are formalized in Rocq.

cs.PL