Tomas Vondra <tomas.vondra@2ndquadrant.com> writes:
> FWIW this apparently happens because the code only expect that
> EquivalenceMembers only contain Var, but in this particular case that's
> not the case - it contains RelabelType (because oprcode is regproc, and
> needs to be relabeled to oid).
If it thinks an EquivalenceMember must be a Var, it's outright broken;
I'm pretty sure any nonvolatile expression is possible.
regards, tom lane