Re: tzcode update

Tom Lane wrote:
> "Heikki Linnakangas" <heikki@enterprisedb.com> writes:
>> Looking closer, I don't understand how that change was supposed to do
>> anything.
>
> The point of that patch is to avoid an off-by-one result for years BC.
> The direction of rounding in integer division with a negative numerator
> is undefined in C (or at least used to be --- did C99 tighten this up?).

Oh, I see. In that case we're good. The corresponding new code in tzcode
  actually looks like this:

> ! static int
> ! leaps_thru_end_of(const int y)
> ! {
> !       return (y >= 0) ? (y / 4 - y / 100 + y / 400) :
> !               -(leaps_thru_end_of(-(y + 1)) + 1);
> ! }


--
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com