A variability-aware module system

Abstract

Module systems enable a divide and conquer strategy to software development. To implement compile-time variability in software product lines, modules can be composed in different combinations. However, this way variability dictates a dominant decomposition. Instead, we introduce a variability-aware module system that supports compile-time variability inside a module and its interface. This way, each module can be considered a product line that can be type checked in isolation. Variability can crosscut multiple modules. The module system breaks with the antimodular tradition of a global variability model in product-line development and provides a path toward software ecosystems and product lines of product lines developed in an open fashion. We discuss the design and implementation of such a module system on a core calculus and provide an implementation for C, which we use to type check the open source product line Busybox with 811 compile-time options.

A comparison of 10 sampling algorithms for configurable systems

“…We computed the ranking of algorithms considering the efficiency function of Section 4.2. The algorithms, starting 7 Variability-aware analysis tools, such as TypeChef [20,21] and Su-perC [15], could soundly cover all configurations regarding syntax or type errors, but would require a time-consuming initial setup that would make our study infeasible. from the most efficient, are: one-enabled, stmt-coverage, onedisabled, pair-wise, most-enabled-disabled, three-wise, random, four-wise, five-wise, and six-wise.…”

“…Gazzillo and Grimm [15] developed a similar parser. In our work, we considered faults detected by TypeChef and reported in previous studies [21]. Difficulties in setting up these tools and narrow classes of detectable faults limit their applicability and lead to false positives.…”

“…Although researchers have proposed approaches to analyze complete configuration spaces in a sound fashion for some classes of defects [15,20,21,53,54], the vast majority of mature quality-assurance techniques consider only a single configuration at a time. For example, static-analysis tools operate typically on C code after the C preprocessor has resolved configuration options implemented through conditional compilation (e.g., using #ifdef directives).…”

Modelling a family of systems for crisis management with concern‐oriented reuse

“…We consider each concern a kind of product line and finally develop product lines of product lines, like in nested product lines [26], multiple product lines [27] or product populations [28]. However, our approach also considers potentially unplanned contexts, like in variable components [29,30] or variability-aware modules [31]. As a result, the reuse of concerns creates a hierarchy of concerns following the hierarchical modularity principle [32].…”

“…In [31], Kästner et al propose a core calculus and C-based implementation for variabilityaware modules with variability handling capabilities inside modules and on module interfaces. Our approach first differs as it aims at supporting hierarchical modularity [32] with concern hierarchies, by the provision of renaming and hiding capabilities and the separate handling of three specific interfaces.…”