As I understand, there has been less than 10 or so non-security bugs each in djbdns and qmail, defined as programming mistakes, not intentional design decisions

As I understand, there has been less than 10 or so non-security bugs each in djbdns and qmail, defined as programming mistakes, not intentional design decisions people disagree with. This is comparable to (or even better than) Knuth. I don't think there is a handy list of bugs though.