Re: Remove dependence on integer wrapping

On Wed, Aug 21, 2024 at 11:37 AM Nathan Bossart <nathandbossart(at)gmail(dot)com>
wrote:
>
> Hm. It seems pretty clear that removing -fwrapv won't be happening
anytime
> soon. I don't mind trying to fix a handful of cases from time to time,
but
> unless there's a live bug, I'm probably not going to treat this stuff as
> high priority.

I think I'm also going to take a step back because I'm a bit
fatigued on the overflow work. My goal here wasn't necessarily to
remove -fwrapv, because I think it will always be a useful safeguard.
Instead I wanted to add -ftrapv to builds with asserts enabled to try
and prevent future overflow based bugs. Though, it looks like that
won't happen anytime soon either.

FWIW, Matthew's patch actually does resolve a bug with `to_timestamp`
and `to_date`. It converts the following incorrect queries

test=# SELECT to_timestamp('2147483647,999', 'Y,YYY');
to_timestamp
---------------------------------
0001-01-01 00:00:00-04:56:02 BC
(1 row)

test=# SELECT to_date('-2147483648', 'CC');
to_date
------------
0001-01-01
(1 row)

into errors

test=# SELECT to_timestamp('2147483647,999', 'Y,YYY');
ERROR: invalid input string for "Y,YYY"
test=# SELECT to_date('-2147483648', 'CC');
ERROR: date out of range: "-2147483648"

So, it might be worth committing only his changes before moving on.

Thanks,
Joseph Koshakow