diff --git a/src/errors.h b/src/errors.h
index 43a1c9b..90aa292 100644
--- a/src/errors.h
+++ b/src/errors.h
@@ -3303,4 +3303,6 @@
 #ifdef FEAT_EVAL
 EXTERN char e_substitute_nesting_too_deep[]
 	INIT(= N_("E1290: substitute nesting too deep"));
+EXTERN char e_invalid_argument_nr[]
+	INIT(= N_("E1291: Invalid argument: %ld"));
 #endif