Re: Revert: Remove useless self-joins *and* -DREALLOCATE_BITMAPSETS make server crash, regress test fail.

Richard Guo <guofenglinux@gmail.com> writes:
> Thank you for the report.  I looked at this a little bit and I think
> here is what happened.  In deconstruct_distribute_oj_quals we call
> distribute_quals_to_rels using the uncopied sjinfo->syn_lefthand as
> outerjoin_nonnullable, which eventually becomes rinfo->outer_relids.
> Later on, when we remove useless left joins, we modify
> sjinfo->syn_lefthand using bms_del_member and recycle
> sjinfo->syn_lefthand.  And that causes the rinfo->outer_relids becomes
> invalid, and finally triggers this issue in join_clause_is_movable_to.

Hmm, the SJE code didn't really touch any of this logic, so why
didn't we see the failure before?

            regards, tom lane