Towards Correct Executable Semantics For Z

There are many ad hoc tools aimed at the animation of executable subsets of the formal specification language Z. This paper presents an approach to rigorously establishing the correctness of such Z animation tools, drawing on ideas from the field of abstract interpretation. Enough of the standard Zsyntax is treated to cover most uses of Z schemas and expressions, after schema calculus constructs have been expanded and embedded schema references replaced

A program construction and verification tool for separation logic

An algebraic approach to the design of program construction and verification tools is applied to separation logic. The control-flow level is modelled by power series with convolution as separating conjunction. A generic construction lifts resource monoids to assertion and predicate transformer quantales. The data domain is captured by concrete storeheap models. These are linked to the separation algebra by soundness proofs. Verification conditions and transformation or refinement laws are derived by equational reasoning within the predicate transformer quantale. This separation of concerns makes an implementation in the Isabelle/HOL proof assistant simple and highly automatic. The resulting tool is itself correct by construction; it is explained on three simple examples.EPSRC grant EP/J003727/1 and the CNPq