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From: Tom Lane <tgl@sss.pgh.pa.us>
To: David Rowley <david.rowley@2ndquadrant.com>
cc: Bruce Momjian <bruce@momjian.us>,
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Subject: Re: Postgres 11 release notes
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Comments: In-reply-to David Rowley <david.rowley@2ndquadrant.com>
	message dated "Tue, 15 May 2018 18:00:41 +1200"
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David Rowley <david.rowley@2ndquadrant.com> writes:
> On 15 May 2018 at 08:28, Bruce Momjian <bruce@momjian.us> wrote:
>> Consistently return <literal>NaN</literal> for
>> <literal>NaN</literal> inputs to <function>power()</literal>
>> on older platforms (Dang Minh Huong)

> While I'm not in favour of removing Dang's credit here, technically
> this patch was Tom's. The code added in float.c by Dang's patch
> (61b200e2f) was effectively reverted by 6bdf1303.  Dang's regression
> tests remain, so should also be credited along with Tom.

I'm not particularly fussed about getting credit for that.  However,
looking again at how that patch series turned out --- ie, that
we ensured POSIX behavior for NaNs only in HEAD --- I wonder
whether we shouldn't do what was mentioned in the commit log for
6bdf1303, and teach numeric_pow() about these same special cases.
It seems like it would be more consistent to change both functions
for v11, rather than letting that other shoe drop in some future
major release.

			regards, tom lane