alt Hacker NewsI always wonder how hardware bugs like this happen with the sheer amount of hardware validation that's done. It'd be fascinating to know how it slipped through the cracks, though I know almost nothing about this side of the industry sadly
Replies
vachina • today at 12:41 PM
The verification plan did not make 0 a bin to cover.
throwawayffffas • today at 1:04 PM
Almost definitely an off by one bug.
bell-cot • today at 1:00 PM
That "sheer amount of hardware validation" is always less-than-perfectly spread across a whole lotta billions of transistors, and combinatorics is a harsh mistress.
RicoElectrico • today at 2:06 PM
Me too. Hardware bugs that arise out of unanticipated module interactions are understandable. But this is a "you had one job" moment.
Validation can't be better than the quality of the specification. Humans don't create comprehensive, unambiguous specifications for the same reasons that we don't write bug-free code, and need formal validation.
Brooks talks about this in _Mythical_Man-Month_... if you really could "just implement the specification", then the specification itself would be complete enough to serve as your code. There will always be bugs in both.