A critique of cyclomatic complexity as a software metric

Abstract

McCabe's cyclomatic complexity metric is widely cited as a useful predictor of various software attributes such as reliability and development effort. This critique demonstrates that it is based upon poor theoretical foundations and an inadequate model of software development. The argument that the metric provides the developer with a useful engineering approximation is not borne out by the empirical evidence. Furthermore, it would appear that for a large class of software it is no more than a proxy for, and in many cases is outperformed by, lines of code.