Re: Overflow hazard in pgbench

Fabien COELHO <coelho@cri.ensmp.fr> writes:
>> I suggest applying the attached in branches that have the required 
>> functions.

> The proposed patch does fix the issue in pgbench TAP test. I'd suggest to 
> add unlikely() on all these conditions, as already done elsewhere. See 
> attached version.

Done that way, though I'm skeptical that it makes any measurable
difference.

> I also recompiled after removing manually -fwrapv: Make check, pgbench TAP 
> tests and check-world all passed. I'm not sure that edge case are well 
> enough tested in postgres to be sure that all is ok just from these runs 
> though.

Yeah, I'm afraid that in most places it'd take a specifically-designed
test case to expose a problem, if there is one.

			regards, tom lane