diff --git a/src/popupwin.c b/src/popupwin.c
index 7883340..6d12c92 100644
--- a/src/popupwin.c
+++ b/src/popupwin.c
@@ -1371,7 +1371,7 @@
 	// "margin_width" is added to "len" where it matters.
 	if (wp->w_width < maxwidth)
 	    wp->w_width = maxwidth;
-	len = win_linetabsize(wp, ml_get_buf(wp->w_buffer, lnum, FALSE),
+	len = win_linetabsize(wp, lnum, ml_get_buf(wp->w_buffer, lnum, FALSE),
 							      (colnr_T)MAXCOL);
 	wp->w_width = w_width;