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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Zhihong Yu <zyu@yugabyte.com>
cc: David Geier <david@swarm64.com>,
        PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: search_plan_tree(): handling of non-leaf CustomScanState nodes
 causes segfault
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Comments: In-reply-to Zhihong Yu <zyu@yugabyte.com>
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Zhihong Yu <zyu@yugabyte.com> writes:
> I was thinking that, if sstate->ss_currentRelation is null for the other
> cases, that would be a bug.
> An assertion can be added for the cases ending with T_TidScanState.

Maybe, but there are surely a lot of other places that would crash
in such a case --- places far more often traversed than search_plan_tree.
I do not see any value in complicating search_plan_tree for that.

			regards, tom lane