Finding Minimal Unsatisfiable Cores of Declarative Specifications

  • Emina Torlak
  • Felix Sheng-Ho Chang
  • Daniel Jackson
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5014)


Declarative specifications exhibit a variety of problems, such as inadvertently overconstrained axioms and underconstrained conjectures, that are hard to diagnose with model checking and theorem proving alone. Recycling core extraction is a new coverage analysis that pinpoints an irreducible unsatisfiable core of a declarative specification. It is based on resolution refutation proofs generated by resolution engines, such as SAT solvers and resolution theorem provers. The extraction algorithm is described, and proved correct, for a generalized specification language with a regular translation to the input logic of a resolution engine. It has been implemented for the Alloy language and evaluated on a variety of specifications, with promising results.


Model Check Conjunctive Normal Form Boolean Formula Alloy Analyzer Minimal Core 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Emina Torlak
    • 1
  • Felix Sheng-Ho Chang
    • 1
  • Daniel Jackson
    • 1
  1. 1.MIT Computer Science and Artificial Intelligence Laboratory 

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