(window_scroll_pixel_based): Exit the move_it_by_lines

loop whenever it stops making progress.

1 files changed, 6 insertions, 1 deletions

diff --git a/src/window.c b/src/window.c
index 2ea7cd1d6dd..3535e50673e 100644
--- a/src/window.c
+++ b/src/window.c
@@ -4154,7 +4154,12 @@ window_scroll_pixel_based (window, n, whole, noerror)
              in the scroll margin at the top.  */
           move_it_to (&it, PT, -1, -1, -1, MOVE_TO_POS);
           while (it.current_y < this_scroll_margin)
-            move_it_by_lines (&it, 1, 1);
+            {
+              int prev = it.current_y;
+              move_it_by_lines (&it, 1, 1);
+              if (prev == it.current_y)
+                break;
+            }
           SET_PT_BOTH (IT_CHARPOS (it), IT_BYTEPOS (it));
         }
       else if (n < 0)