diff --git a/src/drawscreen.c b/src/drawscreen.c
index da0cd13..44c2dc5 100644
--- a/src/drawscreen.c
+++ b/src/drawscreen.c
@@ -2036,7 +2036,7 @@
 			{
 			    colnr_T t;
 
-			    pos.col = STRLEN(ml_get_buf(wp->w_buffer,
+			    pos.col = (int)STRLEN(ml_get_buf(wp->w_buffer,
 							     pos.lnum, FALSE));
 			    getvvcol(wp, &pos, NULL, NULL, &t);
 			    if (toc < t)