Date: Thu, 8 Feb 2024 14:07:37 -0600
From: Nathan Bossart <nathandbossart@gmail.com>
To: Andres Freund <andres@anarazel.de>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Mats Kindahl <mats@timescale.com>,
	Thomas Munro <thomas.munro@gmail.com>,
	Heikki Linnakangas <hlinnaka@iki.fi>,
	pgsql-hackers@lists.postgresql.org
Subject: Re: glibc qsort() vulnerability
Message-ID: <20240208200737.GA504276@nathanxps13>
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On Thu, Feb 08, 2024 at 11:59:54AM -0800, Andres Freund wrote:
> On 2024-02-08 13:44:02 -0500, Tom Lane wrote:
>> Are we okay with using macros that (a) have double evaluation hazards
>> and (b) don't enforce the data types being compared are the same?
>> I think static inlines might be a safer technology.
> 
> +1

Agreed on static inlines.

> I'd put these static inlines into common/int.h. I don't think this is common
> enough to warrant being in c.h. Probably also doesn't hurt to have a not quite
> as generic name as INT_CMP, I'd not be too surprised if that's defined in some
> library.
> 
> 
> I think it's worth following int.h's pattern of including [s]igned/[u]nsigned
> in the name, an efficient implementation for signed might not be the same as
> for unsigned. And if we use static inlines, we need to do so for correct
> semantics anyway.

Seems reasonable to me.

-- 
Nathan Bossart
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