* xdisp.c (reseat_1, Fcurrent_bidi_paragraph_direction): Avoid

undefined behavior by initializing display property bit of a
string processed by the bidirectional iterator.  For details, see
<http://lists.gnu.org/archive/html/emacs-devel/2014-01/msg01920.html>.

src/ChangeLog

+2014-01-24  Dmitry Antipov  <dmantipov@yandex.ru>
+
+	* xdisp.c (reseat_1, Fcurrent_bidi_paragraph_direction): Avoid
+	undefined behavior by initializing display property bit of a
+	string processed by the bidirectional iterator.  For details, see
+	<http://lists.gnu.org/archive/html/emacs-devel/2014-01/msg01920.html>.
+
 2014-01-23  Paul Eggert  <eggert@cs.ucla.edu>
 
 	Minor cleanup of previous change.

src/xdisp.c

@@ -6409,6 +6409,7 @@ reseat_1 (struct it *it, struct text_pos pos, int set_stop_p)
       it->bidi_it.string.s = NULL;
       it->bidi_it.string.lstring = Qnil;
       it->bidi_it.string.bufpos = 0;
+      it->bidi_it.string.from_disp_str = 0;
       it->bidi_it.string.unibyte = 0;
       it->bidi_it.w = it->w;
     }
@@ -20411,6 +20412,7 @@ See also `bidi-paragraph-direction'.  */)
       itb.string.s = NULL;
       itb.string.lstring = Qnil;
       itb.string.bufpos = 0;
+      itb.string.from_disp_str = 0;
       itb.string.unibyte = 0;
       /* We have no window to use here for ignoring window-specific
 	 overlays.  Using NULL for window pointer will cause