Adjust pg_upgrade error message, array freeing, and add error check.

contrib/pg_upgrade/check.c

@@ -362,8 +362,6 @@ check_new_db_is_empty(void)
 		}
 	}
 
-	free_db_and_rel_infos(&new_cluster.dbarr);
-
 	if (found)
 		pg_log(PG_FATAL, "New cluster is not empty; exiting\n");
 }

contrib/pg_upgrade/info.c

@@ -104,6 +104,12 @@ create_rel_filename_map(const char *old_data, const char *new_data,
 	/* new_relfilenode will match old and new pg_class.oid */
 	map->new_relfilenode = new_rel->relfilenode;
 
+	if (strcmp(old_rel->nspname, new_rel->nspname) != 0 ||
+	    strcmp(old_rel->relname, new_rel->relname) != 0)
+		pg_log(PG_FATAL, "mismatch of relation id: database \"%s\", old rel %s.%s, new rel %s.%s\n",
+			old_db, old_rel->nspname, old_rel->relname,
+			new_rel->nspname, new_rel->relname);
+
 	/* used only for logging and error reporing, old/new are identical */
 	snprintf(map->nspname, sizeof(map->nspname), "%s", old_rel->nspname);
 	snprintf(map->relname, sizeof(map->relname), "%s", old_rel->relname);
@@ -141,6 +147,9 @@ get_db_and_rel_infos(ClusterInfo *cluster)
 {
 	int			dbnum;
 
+	if (cluster->dbarr)
+		free_db_and_rel_infos(cluster->dbarr);
+
 	get_db_infos(cluster);
 
 	for (dbnum = 0; dbnum < cluster->dbarr.ndbs; dbnum++)

contrib/pg_upgrade/pg_upgrade.c

@@ -286,7 +286,6 @@ create_new_objects(void)
 	check_ok();
 
 	/* regenerate now that we have objects in the databases */
-	free_db_and_rel_infos(&new_cluster.dbarr);
 	get_db_and_rel_infos(&new_cluster);
 
 	uninstall_support_functions_from_new_cluster();

contrib/pg_upgrade/relfilenode.c

@@ -49,7 +49,7 @@ transfer_all_new_dbs(DbInfoArr *old_db_arr,
 		pageCnvCtx *pageConverter = NULL;
 
 		if (strcmp(old_db->db_name, new_db->db_name) != 0)
-			pg_log(PG_FATAL, "old and new databases have a different names: old \"%s\", new \"%s\"\n",
+			pg_log(PG_FATAL, "old and new databases have different names: old \"%s\", new \"%s\"\n",
 				old_db->db_name, new_db->db_name);
 		
 		n_maps = 0;