Abstract: | A sequence of events is described, leading to the severe deterioration of an initially well conceived and cleanly implemented compiler. It is shown how an initial “optimization” implanted a latent bug in the compiler, how the bug was subsequently activated through innocent compiler modification, and how the compiler then deteriorated because of the incompetent correction of the bus manifestation. This exceedingly negative case history is presented in the hope of conveying to the reader a better feeling for the complex problems inherent to industrial software production and maintenance. The difficulty in proposing any constructive (and complete!) software engineering methodology is known and acknowledged; the study of an episode such as described in this paper might help put the difficulties, with which we are confronted, into better perspective. |