On Mon, Apr 15, 2019 at 06:12:24PM -0400, Tom Lane wrote:
Oh, and as I continue to grep, I found this in dependencies.c:
dependencies = (MVDependencies *) repalloc(dependencies,
offsetof(MVDependencies,
deps)
+ dependencies->ndeps *
sizeof(MVDependency));
I'm pretty sure this is an actual bug: the calculation should be
offsetof(MVDependencies, deps)
+ dependencies->ndeps * sizeof(MVDependency *));
because deps is an array of MVDependency* not MVDependency.
This would lead to an overallocation not underallocation, and it's
probably pretty harmless because ndeps can't get too large (I hope;
if it could, this would have O(N^2) performance problems). Still,
you oughta fix it.
(There's a similar calculation later in the file that gets it right.)
Thanks. I noticed some of the bugs while investigating the recent MCV
serialization, and I plan to fix them soon. This week, hopefully.
regards
--
Tomas Vondra http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
