Re: [sqlsmith] Crash in apply_projection_to_path

On Thu, Apr 28, 2016 at 10:06 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Andreas Seltenreich <seltenreich@gmx.de> writes:
>> the following query against the regression database crashes master as of
>> 23b09e15.
>
>> select 1 from depth0 inner join depth1 on (depth0.c = depth1.c)
>>          where depth0.c @@ depth1.c limit 1;
>
> What's going on here is that add_partial_path is recycling a now-dominated
> partial path without regard for the fact that there's already a GatherPath
> pointing at that old partial path.  Later use of the GatherPath tries to
> make use of its now-dangling subpath pointer.
>
> I'd be inclined to think that it's silly to build GatherPaths in advance
> of having finalized the list of partial paths for a rel.

Uh ... yeah, that shouldn't be happening.  I obviously screwed something up.

-- 
Robert Haas
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