From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@2ndquadrant.com>
cc: Peter <pmc@citylink.dinoex.sub.org>,
        Andrew Gierth <andrew@tao11.riddles.org.uk>,
        pgsql-admin@postgresql.org, pgsql@FreeBSD.org
Subject: Re: Upgrade 10.5->10.6 : db crash BUS ERROR (sig 10), reproducible
In-reply-to: <20190308185001.GA14936@alvherre.pgsql>
References: <20190308185001.GA14936@alvherre.pgsql>
Comments: In-reply-to Alvaro Herrera <alvherre@2ndquadrant.com>
	message dated "Fri, 08 Mar 2019 15:50:01 -0300"
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Content-ID: <22600.1552072405.1@sss.pgh.pa.us>
Date: Fri, 08 Mar 2019 14:13:25 -0500
Message-ID: <22601.1552072405@sss.pgh.pa.us>
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Alvaro Herrera <alvherre@2ndquadrant.com> writes:
> On 2019-Mar-08, Peter wrote:
>> On Fri, Mar 08, 2019 at 02:35:33AM +0000, Andrew Gierth wrote:
>>> ! I'm pretty sure nothing in our buildfarm is i386 without SSE2 though.

>> *laugh* no problem with that. There probably wouldn't be any reason
>> to have such. 

> Actually there *is* a very good reason to have one, which is that we
> would have discovered this bug right away.  (Just ask Tom Lane for a
> tally of bugs that have been discovered due to his old HPUX 10.20
> dinosaur he keeps running just for that purpose).  It seems difficult to
> grab hold of such hardware, however.  I don't suppose you have many
> spare cycles on that machine of yours to run a buildfarm animal?

IIUC, this bug isn't actually down to the old hardware: any SSE-capable
chip ought to exhibit the same problem.  The bug is in the toolchain
somewhere, in that some compiler or run-time infrastructure is failing
to maintain 16-byte stack alignment as required by the ABI.  Or,
possibly, there is disagreement among relevant toolchain elements as
to exactly what ABI they're using.

			regards, tom lane