diff --git a/src/popupwin.c b/src/popupwin.c
index e6792c8..27e9fe1 100644
--- a/src/popupwin.c
+++ b/src/popupwin.c
@@ -1414,7 +1414,7 @@
     }
 
     if (wp->w_firstline < 0)
-	wp->w_topline = lnum > 0 ? lnum + 1 : lnum;
+	wp->w_topline = lnum + 1;
 
     wp->w_has_scrollbar = wp->w_want_scrollbar
 	   && (wp->w_topline > 1 || lnum <= wp->w_buffer->b_ml.ml_line_count);