diff --git a/src/proto/vim9compile.pro b/src/proto/vim9compile.pro
index b2677c8..5486bd9 100644
--- a/src/proto/vim9compile.pro
+++ b/src/proto/vim9compile.pro
@@ -1,5 +1,6 @@
 /* vim9compile.c */
 int check_defined(char_u *p, size_t len, cctx_T *cctx);
+void clear_type_list(garray_T *gap);
 type_T *typval2type(typval_T *tv);
 int check_type(type_T *expected, type_T *actual, int give_msg);
 char_u *skip_type(char_u *start);