AdaCore Blog

Yannick Moy

Yannick Moy is a Senior Software Engineer at AdaCore and co-director of the ProofInUse joint laboratory. At AdaCore, he works on software source code analyzers CodePeer and SPARK, aiming either at detecting bugs or at verifying safety/security properties. Yannick leads the developments of SPARK 2014, a product he presents in articles, conferences, classes and blogs (in particular www.spark-2014.org). Yannick previously worked on source code analyzers for PolySpace (now The MathWorks) and at Université Paris-Sud.

8 entries written by Yannick Moy

by Yannick Moy

(Many) More Low Hanging Bugs

We reported in a previous post our initial experiments to create lightweight checkers for Ada source code, based on the new Libadalang technology. The two checkers we described discovered 12 issues in the codebase of the tools we develop at AdaCore. In this post, we are reporting on 6 more lightweight checkers, which have discovered 114 new issues in our codebase. This is definitely showing that these kind of checkers are worth integrating in static analysis tools, and we look forward to integrating these and more in our static analyzer CodePeer for Ada programs.

#Static Analysis    #Libadalang   

by Yannick Moy, Emmanuel Briot, Nicolas Roche

A Usable Copy-Paste Detector in A Few Lines of Python

After we created lightweight checkers based on the recent Libadalang technology developed at AdaCore, a colleague gave us the challenge of creating a copy-paste detector based on Libadalang. It turned out to be both easier than anticipated, and much more efficient and effective than we could have hoped for. In the end, we hope to use this new detector to refactor the codebase of some of our tools, and we expect to integrate it in our IDEs.

#Libadalang    #Static Analysis    #refactoring   

by Yannick Moy

New Year's Resolution for 2017: Use SPARK, Say Goodbye to Bugs

​NIST has recently published a report called "Dramatically Reducing Software Vulnerabilities"​ in which they single out five approaches which have the potential for creating software with 100 times fewer vulnerabilities than we do today. One of these approaches is formal methods. Among formal methods, the report highlights strong suits of SPARK, and cites SPARK projects as example of mature uses of formal methods. NIST is not the only ones to support the use of SPARK. Editor Bill Wong from Electronic Design has included SPARK in his "2016 Gifts for the Techie". So if your new year's resolutions include software without bugs, have a look at SPARK in 2017.

#VerificationTools    #Formal Methods    #SPARK   

by Yannick Moy

Verified, Trustworthy Code with SPARK and Frama-C

Last week, a few of us at AdaCore have attended a one-day workshop organized at Thales Research and Technologies, around the topic of "Verified, trustworthy code - formal verification of software". Attendees from many different branches of Thales (avionics, railway, security, networks) were given an overview of the state-of-practice in formal verification of software, focused on two technologies: the SPARK technology that we develop at AdaCore for programs in Ada, and the Frama-C technology developed at CEA research labs for programs in C. The most interesting part of the day was the feedback given by three operational teams who have experimented during a few months with either SPARK (two teams) or Frama-C (one team). The lessons learned by first-time adopters of such technologies are quite valuable.

#SPARK    #Formal Methods   

by Yannick Moy

Formal Verification of Legacy Code

Just a few weeks ago, one of our partners reported a strange behavior of the well-known function Ada.Text_IO.Get_Line, which reads a line of text from an input file. When the last line of the file was of a specific length like 499 or 500 or 1000, and not terminated with a newline character, then Get_Line raised an exception End_Error instead of returning the expected string. That was puzzling for a central piece of code known to have worked for the past 10 years! But fair enough, there was indeed a bug in the interaction between subprograms in this code, in boundary cases having to do with the size of an intermediate buffer. My colleague Ed Schonberg who fixed the code of Get_Line had nonetheless the intuition that this particular event, finding such a bug in an otherwise trusted legacy piece of code, deserved a more in depth investigation to ensure no other bugs were hiding. So he challenged the SPARK team at AdaCore in checking the correctness of the patched version. He did well, as in the process we uncovered 3 more bugs.

#SPARK    #Legacy    #Formal Methods   

by Yannick Moy, Jamie Ayre, Emma Adby

Ada Lovelace Bicentennial

The three of us attended the Ada Lovelace Symposium in Oxford (UK). The two days were one fantastic discovery after another about the life, achievements and legacy of Ada Lovelace, the programming pioneer who lent her name to the Ada language.

#Lovelace   

by Yannick Moy

New Book About SPARK 2014

If you're somewhat interested in formal methods applied to software, but you never had the chance to really look at it, now is the time! Prof. John McCormick from University of Northern Iowa and Prof. Peter Chapin from Vermont Technical College have written a truly essential book for getting up to speed with formal verification using SPARK. I really love this book, and here are the aspects I love most:

#SPARK    #Formal Methods    #Teaching   

by Yannick Moy

A Building Code for Building Code

In a recent article in Communications of the ACM, Carl Landwehr, a renowned scientific expert on security, defends the view that the software engineering community is doing overall a poor job at securing our global information system and that this is mostly avoidable by putting what we know works to work, to the point that most vulnerabilities could be completely avoided by design if we cared enough. Shocking! Or so it should appear.

#Ada    #SPARK    #Static Analysis    #Security