On Tue, 7 May 2024 at 17:28, Tom Lane <t...@sss.pgh.pa.us> wrote: > > David Rowley <dgrowle...@gmail.com> writes: > > Yeah, before the revert, that did: > > - sjinf->syn_lefthand = replace_relid(sjinf->syn_lefthand, relid, > > subst); > > That replace code seems to have always done a bms_copy() > > Hmm, not always; see e0477837c.
It was the discussion on that thread that led to the invention of REALLOCATE_BITMAPSETS > What I'm trying to figure out here is whether we have a live bug > in this area in released branches; and if so, why we've not seen > reports of that. We could check what portions of REALLOCATE_BITMAPSETS are backpatchable. It may not be applicable very far back because of v16's 00b41463c. The bms_del_member() would have left a zero set rather than doing bms_free() prior to that commit. There could be a bug in v16. David
