Re: sqlsmith crash incremental sort

On Mon, Apr 13, 2020 at 02:09:43AM +0200, Tomas Vondra wrote:
> Justin, can you try if this resolves the crashes or if there's something
> else going on?

With your patch, this no longer crashes:
|explain SELECT * FROM information_schema.transforms AS ref_1 RIGHT JOIN (SELECT 1 FROM pg_catalog.pg_namespace TABLESAMPLE SYSTEM (7.2))AS sample_2 ON (ref_1.specific_name is NULL);
..and sqlsmith survived 20min, which is a good sign.

pg_ctl -c -D pgsql13.dat start -o '-c port=1234 -c log_min_messages=fatal'
sqlsmith --target='host=/tmp port=1234 dbname=postgres' --verbose

Previously, I changed find_base_rel()'s Assert to an if(){elog}, so I know from
another 12 sqlsmith-hours that there's no other crash occuring frequently.

(I hadn't used sqlsmith before this weekend, and was excited when I first saw
that it'd crashed overnight, and very surprised (after enabling core dumps) to
see that it crashed within ~10min.)

--
Justin