Avoid a risky corner case with invalid face ids.

* src/xdisp.c (handle_stop): Avoid assigning -1 to it->face_id here,
as that creates a dangerous corner case.

2 files changed, 7 insertions, 1 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 0ded1fc7a67..1e28d258523 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,8 @@
 2012-02-12  Chong Yidong  <cyd@gnu.org>
 
+        * xdisp.c (handle_stop): Avoid assigning -1 to it->face_id here,
+        as that creates a dangerous corner case.
+
         * window.c (Fdelete_window_internal): Invalidate the mouse
         highlight (Bug#9904).
 
diff --git a/src/xdisp.c b/src/xdisp.c
index 75ea519e82e..70c12497e20 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -2750,9 +2750,12 @@ init_iterator (struct it *it, struct window *w,
   if (charpos >= BUF_BEG (current_buffer))
     {
       it->end_charpos = ZV;
-      it->face_id = -1;
       IT_CHARPOS (*it) = charpos;
 
+      /* We will rely on `reseat' to set this up properly, via
+         handle_face_prop.  */
+      it->face_id = it->base_face_id;
+
       /* Compute byte position if not specified.  */
       if (bytepos < charpos)
         IT_BYTEPOS (*it) = CHAR_TO_BYTE (charpos);