From: Eli Zaretskii <eliz@gnu.org>
Date: Wed, 17 Jun 2015 17:18:11 +0000 (+0300)
Subject: Avoid infloop in redisplay with tall images
X-Git-Tag: emacs-25.0.90~1718
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=4e53d722ae20544ea3c04ff91052af624ef58175;p=emacs.git

Avoid infloop in redisplay with tall images

* src/xdisp.c (try_scrolling): Prevent an infloop when scrolling
down near ZV.  (Bug#20808)
Call bidi_unshelve_cache to avoid memory leaks.  Use IT_CHARPOS
instead of CHARPOS.
---

diff --git a/src/xdisp.c b/src/xdisp.c
index 7c153302803..25eed01ecfc 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -15094,11 +15094,13 @@ try_scrolling (Lisp_Object window, bool just_this_one_p,
 	    RESTORE_IT (&it, &it, it1data);
 	    move_it_by_lines (&it, 1);
 	    SAVE_IT (it1, it, it1data);
-	  } while (line_bottom_y (&it1) - start_y < amount_to_scroll);
+	  } while (IT_CHARPOS (it) < ZV
+		   && line_bottom_y (&it1) - start_y < amount_to_scroll);
+	  bidi_unshelve_cache (it1data, true);
 	}
 
       /* If STARTP is unchanged, move it down another screen line.  */
-      if (CHARPOS (it.current.pos) == CHARPOS (startp))
+      if (IT_CHARPOS (it) == CHARPOS (startp))
 	move_it_by_lines (&it, 1);
       startp = it.current.pos;
     }