Re: SIGFPE handler is naive

On Mon, Aug 13, 2012 at 11:52 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> On Mon, Aug 13, 2012 at 10:14 PM, Noah Misch <noah(at)leadboat(dot)com> wrote:
>>> Overall, though, I think it best to plug this. We could set a flag before
>>> each operation, like evaluation of SQL arithmetic, for which SIGFPE is normal.
>
>> Yeah, that's what I thought of, too. It seems like it'd be a lot of
>> work to get there, though.
>
> That would depend on how many places there are where SIGFPE is expected.
> Are we sure there are any? Maybe we should just remove the handler and
> let SIGFPE be treated as a core dump.

No clue. According to Wikipedia, it is commonly caused by dividing by
zero, or by dividing by INT_MIN by -1, resulting in a quotient out of
range for the type. I'd be willing to bet that we have got all the
division-by-zero cases patched up just because we try pretty hard to
emit the right error message for such cases, but I'm a lot less
certain that things like INT_MIN/-1 can't happen anywhere.

--
Robert Haas
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