From: Tom Lane <tgl@sss.pgh.pa.us>
To: Thomas Munro <thomas.munro@enterprisedb.com>
cc: Amit Kapila <amit.kapila16@gmail.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
        Heikki Linnakangas <hlinnaka@iki.fi>
Subject: Re: SerializeParamList vs machines with strict alignment
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Comments: In-reply-to Thomas Munro <thomas.munro@enterprisedb.com>
	message dated "Tue, 02 Oct 2018 11:47:48 +1300"
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Date: Mon, 01 Oct 2018 20:01:54 -0400
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Thomas Munro <thomas.munro@enterprisedb.com> writes:
> On Tue, Oct 2, 2018 at 9:49 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Apparently the only somewhat-modern architecture that is resolutely
>> unaligned-unfriendly is MIPS.

> It's been a few years now since I worked on that architecture, but
> Sparc is somewhat-modern and resolutely unaligned-unfriendly.  It's
> just that you can optionally install a trap handler that will do super
> slow non-atomic misaligned access in software instead of blowing up
> with SIGBUS.  With the Sun toolchain you did that explicitly by
> building with -misalign (though it's possible that more recent
> compilers might be doing that without being asked?).

Interesting ... I suppose we'd have seen that on the Sparc critters,
except that they weren't running with force_parallel_mode = regress
like chipmunk is.

Now I'm tempted to propose that Amit commit *just* the test case
and not the fix, and wait a day to see which buildfarm critters fail.

			regards, tom lane