Below is the abstract:

“We present a novel approach for the automatic generation of inductive loop invariants over loops manipulating arrays. Unlike most existing approaches, it generates invariants containing disjunctions and quantifiers, which are rich enough for proving functional properties over programs which manipulate arrays. Our approach does not require the user to provide initial assertions or postconditions. It proceeds by recognizing through static analysis simple code patterns that respect stability properties on accessed locations, on an intermediate representation of parallel assignments. We associate with each pattern a formula that we prove to be a so-called local invariant, and we give conditions for local invariants to compose an inductive invariant of the complete loop. We also give conditions over invariants to be locally maximal, and we show that some of our pattern invariants are indeed maximal.”

Abstract:

We outline the current approach to certification of aircraft software, and the role of the DO-178B guidelines. We consider evidence for its effectiveness and discuss possible explanations for this. We then describe how changes in aircraft systems and in the air traffic system pose new challenges for certification, chiefly by increasing the extent of interaction and integration.

In this position paper we describe the motivations and challenges of analysis and code generation from heterogeneous models when intra-view consistency, optimization and safety are major concerns. We will then introduce Project P and Hi-MoCo – respectively FUI and Eurostars -funded collaborative projects tackling the challenges above. This work continues and extends, in a wider context, the work carried out by the Gene-Auto project. Hereby we will present the key elements of Project P and Hi-MoCo, in particular: (i) the philosophy for the identification of safe and minimal practical subsets of input modeling languages; (ii) the overall architecture of the toolsets, the supported analysis techniques and the target languages for code generation; and finally, (iii) the approach to cross-domain qualification for an open-source, community-driven toolset. The full paper can be downloaded here.

Abstract:
The DO-178C standard improves upon the previous DO-178B version by better supporting newer concepts in software development processes and methods. The new standard contains a core document and four supplements. The core document is an updated version of DO-178B with clarifications, improvements and many known issues addressed. The supplements clarify certification using object oriented technology and related techniques, model based development and verification, formal methods, and software tool qualification considerations. This paper will discuss the new DO-178C guidance for tool qualification and will present an approach to tool qualification based on iterative and agile development methods. Through this approach tools may be qualified at a lower cost and more importantly re-qualified for new software development environments as tools sets (such as compilers) are updated during the main application’s certified development life span.

Full article here.

Visit the Nose Gear Challenge Problem project page on the Open-DO forge.

I was particularly interested in the increasing concern over techniques to address safety and security. Safety is not new in avionics/aerospace, but security is, and both safety and security are quite new for automotive. The key to understanding these concerns is the recent release of new safety certification in both avionics (DO-178C) and automotive (ISO-26262). Both put some emphasis (not at the same level, as one could expect) on static analysis and formal techniques.

Like two years ago, there were many presentations of work on formal methods and modelling, with many formal methods applying to modelling. Next episode in two years!

Under this amazingly explicit name is hiding the formal methods supplement for DO-178C. Or, said otherwise, the document that allows you, as a developer of avionics software, to replace tests/reviews/analyses by formal methods. Or you, as a provider of techniques and tools for formal methods, to find customers in the avionics market. Ah yes, because the new version of the certification standard for avionics software, DO-178C, has been also issued at the same time. So that starts today!

Here is what the abstract of this doc says:

This supplement identifies the additions, modifications and substitutions to DO-178C and DO-278A objectives when formal methods are used as part of a software life cycle, and the additional guidance required. It discusses those aspects of airworthiness certification that pertain to the production of software, using formal methods for systems approved using DO-178C.

Formal methods are mathematically-based techniques for the specification, development and verification of software aspects of digital systems. The mathematical basis of formal methods consists of formal logic, discrete mathematics and computer-readable languages. The use of formal methods is motivated by the expectation that, as in other engineering disciplines, performing appropriate mathematical analyses can contribute to establishing the correctness and robustness of a design.