diff --git a/py/runtime.h b/py/runtime.h
index 54cc60c..59d61e7 100644
--- a/py/runtime.h
+++ b/py/runtime.h
@@ -61,6 +61,7 @@
 void mp_arg_check_num(mp_uint_t n_args, mp_uint_t n_kw, mp_uint_t n_args_min, mp_uint_t n_args_max, bool takes_kw);
 void mp_arg_parse_all(mp_uint_t n_pos, const mp_obj_t *pos, mp_map_t *kws, mp_uint_t n_allowed, const mp_arg_t *allowed, mp_arg_val_t *out_vals);
 void mp_arg_parse_all_kw_array(mp_uint_t n_pos, mp_uint_t n_kw, const mp_obj_t *args, mp_uint_t n_allowed, const mp_arg_t *allowed, mp_arg_val_t *out_vals);
+NORETURN void mp_arg_error_terse_mismatch(void);
 NORETURN void mp_arg_error_unimpl_kw(void);
 
 mp_obj_dict_t *mp_locals_get(void);