From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
cc: David Rowley <dgrowleyml@gmail.com>, sait.nisanci@microsoft.com,
        PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>
Subject: Re: BUG #17158: Distinct ROW fails with Postgres 14
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Comments: In-reply-to Peter Eisentraut <peter.eisentraut@enterprisedb.com>
	message dated "Tue, 14 Sep 2021 16:39:39 +0200"
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Date: Tue, 14 Sep 2021 11:02:13 -0400
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Peter Eisentraut <peter.eisentraut@enterprisedb.com> writes:
> On 10.09.21 21:27, Tom Lane wrote:
>> Perhaps it'd work to put the phony entry into fcinfo->flinfo->fn_mcxt
>> instead of CacheMemoryContext.

> Ok, the attached patch fixes the valgrind error.

Looks roughly sane to me.  I'm of two minds about whether you
ought to change the palloc to palloc0.  We'd have taken much
longer to notice this problem if palloc0 had been used; but
from any standpoint other than "will valgrind catch it", it
seems like zeroing the fake typcache entry would be safer.

			regards, tom lane