Many semantic models of rely-guarantee have been proposed in the literature. This paper proposes a new classification of the approaches into two groups based on their treatment of guarantee conditions. To allow a meaningful comparison, it constructs an abstract model for each group in a unified setting. The first model uses a weaker judgement and supports more general rules for atomic commands ...

The combination of mutable state and pointer aliasing is often troublesome due to non-obvious (and usually unspecified) interferences that may occur between non-local parts of the program. We present a type-based approach to statically control aliasing and mutable state in a minimalistic single-threaded procedural language with support for structures and references. By introducing views, re-com...

The Theme of this special issue is software sustainability—the capability of software systems to endure different types of change over their lifetimes. In our special features, you’ll find a discussion of technical solutions aimed at supporting software changes via robust architectures. While the technical side is undoubtedly important, discussions of software sustainability often get tangled u...

Many models have been proposed to explain the opinion formation in a group of individuals; most of these models study the opinion propagation as the interaction between nodes/agents in a social network. The opinion formation is a very complex process and a realistic model should also take into account the important feedbacks that the opinions of the agents have on the structure of the social ne...

We present assume-guarantee model checking, a novel technique for verifying correctness properties of loosely-coupled multithreaded software systems. Assume-guarantee model checking verifies each thread of a multithreaded system separately by constraining the actions of other threads with an automatically inferred environment assumption. Separate verification of each thread allows the enumerati...

Rely-guarantee is a well-established approach to reasoning about concurrent programs that use parallel composition. However, parallel composition is not how concurrency is structured in real systems. Instead, threads are started by ‘fork’ and collected with ‘join’ commands. This style of concurrency cannot be reasoned about using rely-guarantee, as the life-time of a thread can be scoped dynami...