Re: Strange coding in mvdistinct.c

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.)

            regards, tom lane