Re: Consistent segfault in complex query - Mailing list pgsql-hackers

From Andrew Gierth
Subject Re: Consistent segfault in complex query
Date
Msg-id 87h8iupuo7.fsf@news-spur.riddles.org.uk
Whole thread Raw
In response to Re: Consistent segfault in complex query  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Consistent segfault in complex query  (Andrew Gierth <andrew@tao11.riddles.org.uk>)
List pgsql-hackers
>>>>> "Tom" == Tom Lane <tgl@sss.pgh.pa.us> writes:

 >> There's a relevant commit from Feb this year (ea6d67cf8)
 >> specifically referring to the case of CTEs inside subplans inside
 >> EvalPlanQual, which is exactly the scenario you have in your query.
 >> So you need to try this in 9.3.22 or later (ideally 9.3.24, the
 >> latest) which contain this fix.

 Tom> I'm not entirely convinced that that fix will cure this, but
 Tom> certainly it seems related, and we should find out whether it has
 Tom> any effect.

I agree.

 Tom> The reason this seems possibly different is that we're apparently
 Tom> returning wrong data out of the sub-select (a zero Datum value,
 Tom> but not marked isnull --- if it were, arraycontains wouldn't be
 Tom> reached). The previously fixed bug would have caused either
 Tom> multiple or missed returns of a valid CTE tuple.

I have some ideas as to why, and I'm poking at them in order to create a
test case (no luck yet, but I'll keep at it).

-- 
Andrew (irc:RhodiumToad)


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