diff --git a/src/proto/move.pro b/src/proto/move.pro
index d05eb17..8efecb9 100644
--- a/src/proto/move.pro
+++ b/src/proto/move.pro
@@ -21,6 +21,7 @@
 void validate_cline_row(void);
 void validate_virtcol(void);
 void validate_virtcol_win(win_T *wp);
+void validate_cheight(void);
 void validate_cursor_col(void);
 int win_col_off(win_T *wp);
 int curwin_col_off(void);