>>> Yes: that's what the "record_unwind_protect (save_restriction_restore, 
>>> save_restriction_save ());" does.
>> 
>> So save_restriction_restore will reinstate the buffer in the 
>> narrowing_locks list?
>
> Yes:
>
> Lisp_Object
> save_restriction_save (void)
> {
>  Lisp_Object restr = save_restriction_save_1 ();
>  Lisp_Object locks = narrowing_locks_save ();
>  return Fcons (restr, locks);
> }
>
> void
> save_restriction_restore (Lisp_Object data)
> {
>  narrowing_locks_restore (XCDR (data));
>  save_restriction_restore_1 (XCAR (data));
> }
>

Eli, do you have further comments or objections, or can I install this? 
(Patch attached again for your convenience.)

BTW, I also would like to rename the narrowing_locks_* functions to make 
their names coherent with your change of the name of the macro from 
'with-narrowing' to 'with-restriction'.  I guess that's okay?