diff --git a/src/proto/if_lua.pro b/src/proto/if_lua.pro
index c33678e..2e5da0c 100644
--- a/src/proto/if_lua.pro
+++ b/src/proto/if_lua.pro
@@ -8,4 +8,5 @@
 void lua_window_free(win_T *o);
 void do_luaeval(char_u *str, typval_T *arg, typval_T *rettv);
 int set_ref_in_lua(int copyID);
+void update_package_paths_in_lua(void);
 /* vim: set ft=c : */