In joinpath.c three times we reference "extra_lateral_rels" (with underscores like it's a field), but as far as I can tell that's not a field anywhere in the source code, and looking at the code that follows it seems like it should be referencing "lateral_relids" (and the "extra" is really "extra [in relation to relids]").
Assuming that interpretation is correct, I'd attached a patch to change all three occurrences to "extra lateral_relids" to reduce confusion. Thanks, James
v1-0001-Fix-extra_lateral_rels-typo.patch
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