2004-02-25  Miles Bader  <address@hidden>

	* xdisp.c (check_it): Check string/string_pos consistency.
	(init_iterator): Initialize string-related fields properly.

--- orig/src/xdisp.c
+++ mod/src/xdisp.c
@@ -1905,10 +1905,14 @@
       xassert (STRINGP (it->string));
       xassert (IT_STRING_CHARPOS (*it) >= 0);
     }
-  else if (it->method == next_element_from_buffer)
+  else
     {
-      /* Check that character and byte positions agree.  */
-      xassert (IT_CHARPOS (*it) == BYTE_TO_CHAR (IT_BYTEPOS (*it)));
+      xassert (IT_STRING_CHARPOS (*it) < 0);
+      if (it->method == next_element_from_buffer)
+	{
+	  /* Check that character and byte positions agree.  */
+	  xassert (IT_CHARPOS (*it) == BYTE_TO_CHAR (IT_BYTEPOS (*it)));
+	}
     }
 
   if (it->dpvec)
@@ -2021,6 +2025,8 @@
   it->current.overlay_string_index = -1;
   it->current.dpvec_index = -1;
   it->base_face_id = base_face_id;
+  it->string = Qnil;
+  IT_STRING_CHARPOS (*it) = IT_STRING_BYTEPOS (*it) = -1;
 
   /* The window in which we iterate over current_buffer:  */
   XSETWINDOW (it->window, w);