From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Dean Rasheed <dean.a.rasheed@gmail.com>,
        Michael Paquier <michael@paquier.xyz>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
        =?UTF-8?Q?L=C3=A6titia_Avrot?= <laetitia.avrot@gmail.com>
Subject: Re: pgsql: Add support for hyperbolic functions, as well as log10().
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
	message dated "Wed, 13 Mar 2019 22:22:44 -0400"
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Date: Wed, 13 Mar 2019 22:39:03 -0400
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Robert Haas <robertmhaas@gmail.com> writes:
> On Wed, Mar 13, 2019 at 8:49 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Meh.  As I said before, we're not in the business of improving on what
>> libm does --- if someone has a beef with the results, they need to take
>> it to their platform's libm maintainer, not us.  The point of testing
>> this at all is just to ensure that we've wired up the SQL functions
>> to the library functions correctly.

> Pretty sure we don't even need a test for that.  asinh() isn't going
> to call creat() by mistake.

No, but that's not the hazard.  I have a very fresh-in-mind example:
at one point while tweaking Laetitia's patch, I'd accidentally changed
datanh so that it called tanh not atanh.  The previous set of tests did
not reveal that :-(

			regards, tom lane