From: Eli Zaretskii <eliz@gnu.org>
Date: Sat, 16 Nov 2013 09:27:19 +0000 (+0200)
Subject: Fix bug #15907 with crashes due to after-change-functions.
X-Git-Tag: emacs-24.3.90~173^2^2~42^2~45^2~387^2~812
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=3d6dec8d1ef99202a00c58a6ebdc3aaac7d83de6;p=emacs.git

Fix bug #15907 with crashes due to after-change-functions.

 src/keymap.c (describe_map): Don't crash if PT is 1 both before and
 after inserting the description string.
---

diff --git a/src/ChangeLog b/src/ChangeLog
index f92eb7b85fc..696475c17e5 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2013-11-16  Eli Zaretskii  <eliz@gnu.org>
+
+	* keymap.c (describe_map): Don't crash if PT is 1 both before and
+	after inserting the description string.  (Bug#15907)
+
 2013-11-15  Paul Eggert  <eggert@cs.ucla.edu>
 
 	* data.c: Work around bogus GCC diagnostic about shift count.
diff --git a/src/keymap.c b/src/keymap.c
index 7a18cd5d983..562787ee8a5 100644
--- a/src/keymap.c
+++ b/src/keymap.c
@@ -3383,9 +3383,12 @@ describe_map (Lisp_Object map, Lisp_Object prefix,
 
       if (vect[i].shadowed)
 	{
-	  SET_PT (PT - 1);
+	  ptrdiff_t pt = max (PT - 1, BEG);
+
+	  SET_PT (pt);
 	  insert_string ("\n  (that binding is currently shadowed by another mode)");
-	  SET_PT (PT + 1);
+	  pt = min (PT + 1, Z);
+	  SET_PT (pt);
 	}
     }