From: Tom Lane <tgl@sss.pgh.pa.us>
To: Michael Paquier <michael@paquier.xyz>
cc: Bruce Momjian <bruce@momjian.us>, Robert Haas <robertmhaas@gmail.com>,
        Peter Geoghegan <pg@bowt.ie>,
        Matthias van de Meent <boekewurm+postgres@gmail.com>,
        PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Subject: Re: Preventing indirection for IndexPageGetOpaque for known-size page
 special areas
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Comments: In-reply-to Michael Paquier <michael@paquier.xyz>
	message dated "Tue, 29 Nov 2022 09:22:22 +0900"
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Date: Mon, 28 Nov 2022 19:48:54 -0500
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Michael Paquier <michael@paquier.xyz> writes:
> I am wondering if it would be worth adding an AssertMacro() like in
> this one, though:
> https://www.postgresql.org/message-id/YkaP64JvZTMgcHtq@paquier.xyz

Kind of doubt it.  It'd bloat debug builds with a lot of redundant
checks, and probably never catch anything.  For catching problems
in production, the right place to do this (and where we already do
do it) is in _bt_checkpage.

If any of the other AMs lack page-read-time sanity checks like
_bt_checkpage, I'd be in favor of adding that.  But I don't
think a whole bunch of additional checks afterwards will buy much.

			regards, tom lane