Overflow is "undefined" in the sense that it might give you a different result on different platforms.

My money is on this being an array bounds error in PDL's connected-component labeling routine. That's an interesting topic, check out the link.

In reply to Re: [maybe OT] What kind of bug was that? Non-deterministic result with C integer overflow? by Anonymous Monk
in thread [maybe OT] What kind of bug was that? Non-deterministic result with C integer overflow? by vr

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