diff --git a/src/proto/screen.pro b/src/proto/screen.pro
index 919bd41..3f475ec 100644
--- a/src/proto/screen.pro
+++ b/src/proto/screen.pro
@@ -31,6 +31,7 @@
 void screenalloc(int doclear);
 void free_screenlines(void);
 void screenclear(void);
+void line_was_clobbered(int screen_lnum);
 int can_clear(char_u *p);
 void screen_start(void);
 void windgoto(int row, int col);