Krakatoa and Jessie: verification tools for Java and C programs

Overview

Krakatoa and Jessie are two front-ends of the Why platform for deductive program verification. Krakatoa deals with Java programs annotated in a variant of the The Java Modeling Language. Jessie deals with C programs annotated in the ANSI/ISO C Specification Language (ACSL). Technically, Jessie denotes two things: an intermediate language common to C and Java, and a plugin of the Frama-C environment which compiles ACSL-annotated C code into the Jessie intermediate language. The relationship between these tools are illustrated by the picture on the right.
Downloading
Krakatoa and Jessie, including the Frama-C plugin, are distributed together with Why version 2.34. Follow this link for older versions. To install external provers, please see the specific section below.
Relationship with Why3
The development of Why is now frozen, meaning that future releases might be provided e.g. for compatibility with newer versions of Frama-C, but no new feature will appear anymore. The development of Why continues in the context of a completely new system Why3. The foundations of Why3, including new features, are presented in François Bobot, Jean-Christophe Filliâtre, Claude Marché and Andrei Paskevich. Why3: Shepherd your herd of provers. In Boogie 2011: First International Workshop on Intermediate Verification Languages, Wroclaw, Poland, August 2011.

However, Why3 does not have its own front-ends for C or Java yet. For the moment, to smoothly encourage users to move to Why3, Krakatoa and Jessie have been given the option to generate intermediate code for the Why3 VC generator. It is thus recommended to install Why3 conjointly with Why version 2.34. See the respective manuals of Krakatoa and Jessie for details. The table below summarizes the compatibility between Frama-C, Why 2.xx and Why3 versions

Frama-C Why Why3 remarks
Carbon-20110201 2.29 0.64 very preliminary support for Why3 output, i.e. only -jessie-atp=why3ide or why3
Nitrogen-20111001 2.30 0.71 Output through Why3 VC generator and IDE is now the default, use former option -jessie-atp=gui to obtain the former behavior calling Why 2.xx VC gen
Nitrogen-20111001 2.31 0.72 or 0.73 0.73 is recommended
Oxygen-20120901 2.32 0.81
Fluorine-20130[4-6]01 2.33 0.81
Neon-20140301 2.34 0.83

Regarding Java source files, in version 2.30 and higher, the command gwhy File.java continues to call the former Why VCgen and gwhy interface, whereas krakatoa File.java now calls the Why3 VCgen and GUI. The former behavior of the krakatoa command is obtained using the new option -gen-only.
Other resources

Jessie plugin of Frama-C

Jessie is a plugin of the Frama-C environment for static analysis of C code. It aims at deductive verification of behavioral properties of the code, specified using the ACSL language.

Documentation, including a tutorial and a reference manual, is available in PDF format or in online HTML.

Other resources:

Krakatoa

Krakatoa is a verification tool for Java programs. It is a tool from the Why platform for deductive program verification.

Documentation, including a tutorial and a reference manual, is available in PDF format or in online HTML.

Other resources:

Installing external provers

This page gives a few tips to download, install and/or configure external provers. Each time a new prover is installed, you must rerun the command why-config (in Why 2.xx) and/or why3config --detect (in Why3). Using the latest version is recommended (except for Yices, see below) and the config tool above will tell you if the version detected is supported or not.
Automatic provers
Alt-Ergo
available under binary form for Unix, or under source form to be compiled using the OCaml compiler, from this page. A Microsoft Windows installer is also available.
CVC3
available under source form and as a Linux binary from this page
E-prover (Why3 only)
available under source form as well as some binary format from this page
Gappa
a prover specialized on verification of numeric formulas, including floating-point numbers, available under source form at this page
Simplify
available under binary form for various architectures from this page or directly here
SPASS (Why3 only)
available under source form as well as some binary format from this page
Vampire (Why3 only)
available under some binary format from this page
veriT
available under source form from this page
Yices
available under binary form for various platform from this page. (Note that Yices version 2 which participated to the SMT-COMP 2009 has no support for quantifiers; thus you should not use it with Why.)
Z3
available under binary format for Microsoft Windows as well as linux from this page
Interactive provers, Proof assistants
The Coq proof assistant
The PVS specification and verification system
(Why 2.xx only for the moment)
Isabelle/HOL
(Why 2.xx only for the moment)
HOL 4
(Why 2.xx only for the moment)
HOL Light
(Why 2.xx only for the moment)
Mizar
(Why 2.xx only for the moment)

20/4/2013