Andres Freund <andres(at)2ndquadrant(dot)com> writes:
> On Friday, June 22, 2012 04:41:20 PM Tom Lane wrote:
>> Well, so does list.c, so I'd expect the performance risks to be similar.
> I don't think list.c does so:
Huh, OK. I seem to remember that the original version actually chased
down the whole list and verified that the length matched. We must've
soon decided that that was insupportable in practice. There might be
a lesson here for your checks.
regards, tom lane