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Two flavors of DRAT

EasyChair Preprint 457

17 pagesDate: August 25, 2018

Abstract

DRAT proofs have become the de facto standard for certifying SAT solvers' results. State-of-the-art DRAT checkers are able to efficiently establish the unsatisfiability of a formula. However, DRAT checking requires unit propagation, and so it is computationally non-trivial. Due to design decisions in the development of early DRAT checkers, the class of proofs accepted by state-of-the-art DRAT checkers differs from the class of proofs accepted by the original definition. In this paper, we formalize the operational definition of DRAT proofs, and discuss practical implications of this difference for generating as well as checking DRAT proofs. We also show that these theoretical differences have the potential to affect whether some proofs generated in practice by SAT solvers are correct or not.

Keyphrases: DRAT proofs, Unsatisfiability proof generation, backwards checking, proof checking, watched literal schema

BibTeX entry
BibTeX does not have the right entry for preprints. This is a hack for producing the correct reference:
@booklet{EasyChair:457,
  author    = {Adrián Rebola-Pardo and Armin Biere},
  title     = {Two flavors of DRAT},
  doi       = {10.29007/nnqs},
  howpublished = {EasyChair Preprint 457},
  year      = {EasyChair, 2018}}
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