The Role of Inspection in Software Quality Assurance

DESPITE more than 30 years of effort to improve its quality, software is still released with many errors. Many major products are known to have thousands of bugs. It is not for lack of trying; all major software developers have a software quality assurance effort and attempt to remove bugs before release. The problem is the complexity of the code. It is very easy to review code but fail to notice significant errors. Researchers have responded to these problems by studying methods of formal correctness verification for programs. In theory, we now know how to prove programs correct with the same degree of rigor that we apply to mathematical theorems. In fact, this is rarely practical and even more rarely done. Most research papers on verification make simplifying assumptions (e.g., a 1:1 correspondence between variables and variable names) that are not valid for real programs. Proofs of realistic programs involve long complex expressions and require patience, time, and diligence that developers do not think that they have. (Interestingly enough, they never have time to verify the program before release, but they must take time to respond to complaints after release.) Inspection methods can be more effective than informal reviews and require less effort than formal proof, but success depends on having a sound and systematic procedure for conducting the inspection. Tools that support this procedure are also important. The Workshop on Inspection in Software Engineering (WISE), a satellite event of the 2001 Computer Aided Verification (CAV ’01) Conference, brought together researchers, practitioners, and regulators in the hope of finding new, more effective approaches to software inspection. The workshop included invited lectures and paper presentations in the form of panel discussions on all aspects of software inspection. Submissions explained how practitioners and researchers were performing inspections, discussed the relevance of inspections, provided evidence of how inspections could be improved though refinement of the inspection process and computer aided tool support and explained how careful design of software could make inspections easier or more effective. The best ideas from the workshop have been distilled into pairs of papers appearing in linked special issues of IEEE Software Magazine (Software) and IEEE Transactions on Software Engineering (TSE).