Not necessarily, which is why I've always disliked the term, even apart from how it's used so often as to be meaningless rhetoric. Plenty of people might take "fake" to mean false, regardless of intent. And I would also argue that "fake news" can also be interpreted to mean that something mundane/previously known is falsely insinuated to be shocking "news" e.g. "Barack Obama discovered to have lived with single white teen mom", which is technically true (his mother was white and living alone at the time of his birth), but the intent of the headline is obviously to imply scandal.

That said, I don't think it's normal for a "software bug" to result in such an egregious error as to require a retraction of the study. I'd like to know why the peer review process failed to detect the problem.