From: Tom Lane <tgl@sss.pgh.pa.us>
To: Dean Rasheed <dean.a.rasheed@gmail.com>
cc: Yugo NAGATA <nagata@sraoss.co.jp>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Numeric x^y for negative x
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Comments: In-reply-to Dean Rasheed <dean.a.rasheed@gmail.com>
	message dated "Thu, 29 Jul 2021 19:14:05 +0100"
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Date: Thu, 05 Aug 2021 12:04:39 -0400
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Dean Rasheed <dean.a.rasheed@gmail.com> writes:
> On Thu, 22 Jul 2021 at 16:19, Dean Rasheed <dean.a.rasheed@gmail.com> wr=
ote:
>> Thanks for looking. Barring any further comments, I'll push this in a f=
ew days.

> So I have been testing this a lot over the last couple of days, and I
> have concluded that the patch works well as far as it goes, but I did
> manage to construct another case where numeric_power() loses
> precision. I think, though, that it would be better to tackle that as
> a separate patch.

It looks like castoroides is not happy with this patch:

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=3Dcastoroides&dt=3D=
2021-08-01%2008%3A52%3A43

Maybe there's some hidden C99 dependency in what you did?
Although pademelon, which is one of our other pre-C99
dinosaurs, doesn't seem to be unhappy.

			regards, tom lane