From: Tom Lane <tgl@sss.pgh.pa.us>
To: Melanie Plageman <melanieplageman@gmail.com>
cc: Fujii Masao <masao.fujii@gmail.com>, Robert Haas <robertmhaas@gmail.com>,
        Andrey Borodin <x4mmm@yandex-team.ru>,
        Andres Freund <andres@anarazel.de>,
        Matthias van de Meent <boekewurm+postgres@gmail.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
        Heikki Linnakangas <hlinnaka@iki.fi>
Subject: Re: Why clearing the VM doesn't require registering vm buffer in wal
 record
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Comments: In-reply-to Melanie Plageman <melanieplageman@gmail.com>
	message dated "Fri, 17 Jul 2026 16:51:46 -0400"
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Date: Sun, 19 Jul 2026 22:34:29 -0400
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Melanie Plageman <melanieplageman@gmail.com> writes:
> I've committed this.

Coverity complained about this patch:

/srv/coverity/git/pgsql-git/postgresql/src/backend/access/heap/pruneheap.c=
: 951             in heap_page_fix_vm_corruption()
945             MarkBufferDirtyHint(prstate->buffer, true);
946         }
947     =

948         if (do_clear_vm)
949         {
950             LockBuffer(prstate->vmbuffer, BUFFER_LOCK_EXCLUSIVE);
>>>     CID 1697133:         Error handling issues  (CHECKED_RETURN)
>>>     Calling "visibilitymap_clear" without checking return value (as is=
 done elsewhere 13 out of 14 times).
951             visibilitymap_clear(prstate->relation->rd_locator, prstate=
->block,
952                                 prstate->vmbuffer,
953                                 VISIBILITYMAP_VALID_BITS);
954             LockBuffer(prstate->vmbuffer, BUFFER_LOCK_UNLOCK);
955             prstate->old_vmbits =3D 0;
956         }

I think it's right to complain --- if we check for failure everywhere
else, why's it OK to not check here?  If it is OK, a comment and an
explicit cast to "(void)" would be appropriate.

			regards, tom lane