From: Tom Lane <tgl@sss.pgh.pa.us>
To: Amit Langote <amitlangote09@gmail.com>
cc: Tender Wang <tndrwang@gmail.com>, Michael Paquier <michael@paquier.xyz>,
        exclusion@gmail.com, pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #18657: Using JSON_OBJECTAGG with volatile function leads to
 segfault
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Comments: In-reply-to Amit Langote <amitlangote09@gmail.com>
	message dated "Wed, 16 Oct 2024 21:00:19 +0900"
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Date: Wed, 16 Oct 2024 10:26:39 -0400
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Amit Langote <amitlangote09@gmail.com> writes:
> Also, it might be better to leave a comment where the commit is
> removing code, as follows:

> -                if (WALK(jve->raw_expr))
> -                    return true;
> +                /* Ignore raw_expr because it's not relevant at runtime. */

Would it be better for parse analysis to explicitly NULL out this
field once it's done looking at it?  Carrying unmaintained pieces
of an expression tree around seems both inefficient and prone to
future failures of this same ilk.  The further the raw_expr gets
out of step with current reality, the worse the hazards.

			regards, tom lane