jit-lock called at EOB?

[Stefan Monnier <monnier@iro.umontreal.ca>]

The recent problems of "looping in jit-lock / redisplay" seem to be caused
by the fact that every redisplay will call jit-lock at EOB because the
text-property value of `fontified' at EOB is always nil (this is because
get-text-property treats requests at EOB specially: there is no char there,
so there can't be a property either, but instead of signalling an error it
returns nil).

I've worked around this problem now in jit-lock by ignoring requests to
fontify empty regions of text, but I believe the real bug is in the C code
which shouldn't call jit-lock at all.  So I suggest the patch below.

Any objection?


        Stefan


--- xdisp.c	22 sep 2006 11:15:42 -0400	1.1122
+++ xdisp.c	28 sep 2006 10:28:50 -0400	
@@ -3246,7 +3246,9 @@
       && !NILP (Vrun_hooks)
       && (pos = make_number (IT_CHARPOS (*it)),
 	  prop = Fget_char_property (pos, Qfontified, Qnil),
-	  NILP (prop)))
+	  /* Ignore the special cased nil value always present at EOB since
+	     no amount of fontifying will be able to change it.  */
+	  NILP (prop) && IT_CHARPOS (*it) < Z))
     {
       int count = SPECPDL_INDEX ();
       Lisp_Object val;