diff --git a/src/proto/message.pro b/src/proto/message.pro
index 6657a08..54a0a77 100644
--- a/src/proto/message.pro
+++ b/src/proto/message.pro
@@ -73,6 +73,7 @@
 void give_warning_with_source(char_u *message, int hl, int with_source);
 void give_warning2(char_u *message, char_u *a1, int hl);
 void msg_advance(int col);
+void msg_warn_missing_clipboard(void);
 int do_dialog(int type, char_u *title, char_u *message, char_u *buttons, int dfltbutton, char_u *textfield, int ex_cmd);
 int vim_dialog_yesno(int type, char_u *title, char_u *message, int dflt);
 int vim_dialog_yesnocancel(int type, char_u *title, char_u *message, int dflt);