set_deparse_plan: Reuse variable to appease Coverity

Coverity complains that dpns->outer_plan is deferenced (to obtain ->targetlist) when possibly NULL. We can avoid this by using dpns->outer_tlist instead, which was already obtained a few lines up. The fact that we end up with dpns->inner_tlist = dpns->outer_tlist is a bit suspicious-looking and maybe worthy of more investigation, but I'll leave that for another day. Reviewed-by: Michaël Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/202204191345.qerjy3kxi3eb@alvherre.pgsql

Author: alvherre

src/backend/utils/adt/ruleutils.c

@@ -4996,7 +4996,7 @@ set_deparse_plan(deparse_namespace *dpns, Plan *plan)
 if (IsA(plan, ModifyTable))
 {
 if (((ModifyTable *) plan)->operation == CMD_MERGE)
-dpns->inner_tlist = dpns->outer_plan->targetlist;
+dpns->inner_tlist = dpns->outer_tlist;
 else
 dpns->inner_tlist = ((ModifyTable *) plan)->exclRelTlist;
 }