bug#8998: culprit found

[emacs18]

I think the infinite loop problem that I reported was introduced by
revision 104853 shown below.


=== modified file 'lisp/ChangeLog'
--- lisp/ChangeLog      2011-07-01 13:37:00 +0000
+++ lisp/ChangeLog      2011-07-01 16:41:02 +0000
@@ -1,3 +1,8 @@
+2011-07-01  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+       * emacs-lisp/derived.el (define-derived-mode): Make abbrev-table
+       inherit from parent.
+
 2011-07-01  Lars Magne Ingebrigtsen  <larsi@gnus.org>
 
        * dired-aux.el (dired-diff): Doc fixup (bug#8816).

=== modified file 'lisp/emacs-lisp/derived.el'
--- lisp/emacs-lisp/derived.el  2011-03-22 20:58:27 +0000
+++ lisp/emacs-lisp/derived.el  2011-07-01 16:41:02 +0000
@@ -253,8 +253,11 @@
                   `(let ((parent (char-table-parent ,syntax)))
                      (unless (and parent
                                   (not (eq parent (standard-syntax-table))))
-                       (set-char-table-parent ,syntax (syntax-table)))))))
-
+                       (set-char-table-parent ,syntax (syntax-table)))))
+                ,(when declare-abbrev
+                   `(unless (abbrev-table-get ,abbrev :parents)
+                      (abbrev-table-put ,abbrev :parents
+                                        (list local-abbrev-table))))))
          (use-local-map ,map)
          ,(when syntax `(set-syntax-table ,syntax))
          ,(when abbrev `(setq local-abbrev-table ,abbrev))