From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@alvh.no-ip.org>
cc: XChy <xxs_chy@outlook.com>, pgsql-general@postgresql.org
Subject: Re: Missed compiler optimization issue in function select_rtable_names_for_explain
In-reply-to: <202405221100.fy66dsew2f52@alvherre.pgsql>
References: <202405221100.fy66dsew2f52@alvherre.pgsql>
Comments: In-reply-to Alvaro Herrera <alvherre@alvh.no-ip.org>
	message dated "Wed, 22 May 2024 13:00:12 +0200"
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Date: Wed, 22 May 2024 16:05:32 -0400
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Alvaro Herrera <alvherre@alvh.no-ip.org> writes:
> I think if we want to improve how this code is seen by the compiler by
> modifying it, we should just remove the NULL/NIL assignments.  It's a
> pretty arbitrary (and rather small) subset of fields being initialized,
> fields which very obviously have been zeroed by memset already, so I
> don't see any value in the explicit assignments.

I have to concede that it's unclear why we're filling just these
fields explicitly and not any others.  We're at least consistent:
all the callers of select_rtable_names do it the same way.

			regards, tom lane