cfaed Seminar Series
cfaed Seminar Series
Andrzej Wasowski , IT University of Copenhagen
Variability Bugs in Linux and Similar Projects
, 11:00 - 12:00
Andreas-Pfitzmann-Bau, room 1004 , Nöthnitzer Str. 46 , 01187 Dresden
During his visit on the occasion of the dissertation defence of Christoph Seidl, his external supervisor, associate professor Andrzej Wasowski of the IT University of Copenhagen, will present a talk on "Variability Bugs in Linux and Similar Projects".
You are kindly invited to this talk that will take place on Feb 22, 11:00-12:00, room 1004, Andreas-Pfitzmann-Bau.
Variability-sensitive verification pursues effective analysis of the exponentially many variants in number of features of a program family. Several variability-aware techniques have been proposed, but researchers still lack examples of concrete bugs induced by variability, occurring in real large-scale systems. A collection of real world bugs is needed to evaluate tool implementations of variability-sensitive analyses by testing them on real bugs. The talk will present a qualitative study of almost 100 diverse variability bugs collected from bug-fixing commits in the Apache, BusyBox, Linux kernel and Marlin repositories. The researchers analyze each of the bugs, and record the results in a database. For each bug, they create a self-contained simplified C99 version and a simplified patch, in order to help researchers who are not experts on these subject studies to understand them, so that they can use it for evaluation of their tools. In addition, they provide single-function versions of the bugs, which are useful for evaluating intra-procedural analyses. A Web-based User Interface for the database allows to conveniently browse and visualize the collection of bugs. The study provides insights into the nature and occurrence of variability bugs in four highly-configurable systems implemented in C, and shows in what ways variability affects and increases the complexity of software bugs.
Time permitting, the lecture shall comment on what might be the reasons for these bugs to appear, summarizing a recently completed controlled experiment that investigated correlations between variability and ability of programmers to find bugs in code.
This is joint work with Iago Abal, Claus Brabrand, Jean Melo,Stefan Stanciulescu and Marcio Ribeiro.
Andrzej Wasowski is associate professor at IT University of Copenhagen. His interests are in model-driven software development, software product-lines and applied program (and model) analysis.