diff --git a/src/errors.h b/src/errors.h
index 5a59f7f..d12eb9f 100644
--- a/src/errors.h
+++ b/src/errors.h
@@ -3426,4 +3426,10 @@
 	INIT(= N_("E1350: Duplicate \"implements\""));
 EXTERN char e_duplicate_interface_after_implements_str[]
 	INIT(= N_("E1351: Duplicate interface after \"implements\": %s"));
+EXTERN char e_duplicate_extends[]
+	INIT(= N_("E1352: Duplicate \"extends\""));
+EXTERN char e_class_name_not_found_str[]
+	INIT(= N_("E1353: Class name not found: %s"));
+EXTERN char e_cannot_extend_str[]
+	INIT(= N_("E1354: Cannot extend %s"));
 #endif