close_ps, NULLs, and DirectFunctionCall
(From IRC discussion with Andreas about some sqlsmith errors)
Commit 278148907a9 changed close_ps in geo_ops.c to return SQL NULL in
the event that a valid result point was not found (rather than crashing
or failing an assert).
But close_ps is called with DirectFunctionCall from other close_*
functions, and indirectly from dist_* functions. So while the specific
case of (point ## lseg) returns a NULL with no error in this case, for
other data types, or for certain dist_* calls, rather than a null result
you get this:
postgres=# select point(1,2) ## '((0,0),(NaN,NaN))'::box;
ERROR: function 0x9c5de0 returned NULL
postgres=# select point(1,2) <-> '((0,0),(NaN,NaN))'::box;
ERROR: function 0x9c5de0 returned NULL
This seems ... unhelpful (though it's at least better than crashing) and
inconsistent.
Does this need fixing, and if so how? The most consistent fix would seem
to be to make all the affected functions return NULL, which probably
requires factoring out a bunch of close_*_internal functions and
replacing the DirectFunctionCall usage.
--
Andrew (irc:RhodiumToad)
--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers
Does this need fixing, and if so how?
My improve geometric types patch [1]/messages/by-id/CAE2gYzxF7-5djV6-cEvqQu-fNsnt=EqbOURx7ZDg+Vv6ZMTWbg@mail.gmail.com fixes this issue, by cosidering
NaNs larger than any non-NAN same as the float types. There are many
issues with the geometric types similar to this. Let's combine our
efforts to put them into a shape.
[1]: /messages/by-id/CAE2gYzxF7-5djV6-cEvqQu-fNsnt=EqbOURx7ZDg+Vv6ZMTWbg@mail.gmail.com
--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers
On Wed, Sep 20, 2017 at 4:25 PM, Andrew Gierth
<andrew@tao11.riddles.org.uk> wrote:
postgres=# select point(1,2) ## '((0,0),(NaN,NaN))'::box;
ERROR: function 0x9c5de0 returned NULLpostgres=# select point(1,2) <-> '((0,0),(NaN,NaN))'::box;
ERROR: function 0x9c5de0 returned NULLThis seems ... unhelpful (though it's at least better than crashing) and
inconsistent.
I'd call that a bug.
The most consistent fix would seem
to be to make all the affected functions return NULL,
Based on your description of the problem I would tend to agree,
although I'm not really familiar with this area.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers