-ruleLhsFreeNames :: CoreRule -> NameSet
-ruleLhsFreeNames (BuiltinRule { ru_fn = fn }) = unitNameSet fn
-ruleLhsFreeNames (Rule { ru_fn = fn, ru_args = tpl_args })
- = addOneToNameSet (exprsFreeNames tpl_args) fn
+ruleLhsOrphNames :: CoreRule -> NameSet
+ruleLhsOrphNames (BuiltinRule { ru_fn = fn }) = unitNameSet fn
+ruleLhsOrphNames (Rule { ru_fn = fn, ru_args = tpl_args })
+ = addOneToNameSet (exprsOrphNames tpl_args) fn
+ -- No need to delete bndrs, because
+ -- exprsOrphNames finds only External names