Re: gcc versus division-by-zero traps

Tom Lane wrote:
> I hope that the bug will get fixed in due course, but even if they
> respond pretty quickly it will be years before the problem disappears
> from every copy of gcc in the field. So I'm thinking that it would
> behoove us to install a workaround, now that we've characterized the
> problem sufficiently. What I am thinking is that in the three
> functions known to exhibit the bug (int24div, int28div, int48div)
> we should do something like this:
>
>
> if (arg2 == 0)
> + {
> ereport(ERROR,
> (errcode(ERRCODE_DIVISION_BY_ZERO),
> errmsg("division by zero")));
> + /* ensure compiler realizes we don't reach the division */
> + PG_RETURN_NULL();
> + }

Could we document this a little better, perhaps refer to a file
somewhere or a central comment on its purpose?

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Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

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