diff --git a/src/proto/vim9cmds.pro b/src/proto/vim9cmds.pro
index 10fc2c7..79a1557 100644
--- a/src/proto/vim9cmds.pro
+++ b/src/proto/vim9cmds.pro
@@ -21,6 +21,7 @@
 char_u *compile_endtry(char_u *arg, cctx_T *cctx);
 char_u *compile_throw(char_u *arg, cctx_T *cctx);
 char_u *compile_eval(char_u *arg, cctx_T *cctx);
+int get_defer_var_idx(cctx_T *cctx);
 char_u *compile_defer(char_u *arg_start, cctx_T *cctx);
 char_u *compile_mult_expr(char_u *arg, int cmdidx, cctx_T *cctx);
 char_u *compile_put(char_u *arg, exarg_T *eap, cctx_T *cctx);