KeY’s SED Successfully Applied in an Industrial Setting

The Symbolic Execution Debugger (SED) is a debugging and visualization tool based on KeY’s symbolic execution engine that can be used, just like a standard debugger, without any specialist knowledge. Now, the SED has successfully been applied by Aniket Kulkarni from Tata Consultancy Services in the validation of an industrial software component. He concludes that the “SED tool is useful for applying Symbolic Execution techniques as visual feedback is given to the developer”.

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Proving JDK’s Dual Pivot Quicksort Correct

by Bernhard Beckert, Jonas Schiffl, Peter H. Schmitt and Mattias Ulbrich

Sorting is a fundamental functionality in libraries, for which efficiency is crucial. Correctness of the highly optimized implementations is often taken for granted. De Gouw et al. have shown that this certainty is deceptive by revealing a bug in the Java Development Kit (JDK) implementation of TimSort.

We have now formally analysed the other implementation of sorting in the JDK standard library: A highly efficient implementation of a dual pivot quicksort algorithm. We were able to deductively prove that the algorithm implementation is correct. However, a loop invariant which is annotated to the source code does not hold. Continue reading “Proving JDK’s Dual Pivot Quicksort Correct”