[O] Bug: new latex exporter, 'Stack overflow in equal' with identical headings

[Myles English]

To reproduce:

1.   copy the ECM below to a buffer
2.   execute the lisp block
3.   "M-x org-export-dispatch RET l"

I would expect the orgmode doc to be exported to a latex buffer.  What
results is an error and the message "cdr: Stack overflow in equal bug"

My setup: started with 'emacs -Q' and with a recent git checkout at
~/.emacs.d/plugins/org-mode:
 commit 9028c4655f2d7f925de1e3ad6471900c78a8c000
 Date:   Tue Jul 10 15:30:51 2012 +0200

The error is caused by having two headings the same, although at
different levels, and both containing a backslash.

== begin org file ==
#+TITLE:     "Stack overflow in equal" ECM
#+OPTIONS: ^:{}

#+begin_src elisp
(add-to-list 'load-path
             "~/.emacs.d/plugins/org-mode/lisp")
(require 'org-install)
(add-to-list 'load-path
             "~/.emacs.d/plugins/org-mode/contrib/lisp")
(require 'org-export)
(require 'org-e-latex)
#+end_src

#+RESULTS:
: org-e-latex

* Heading One

** \cite{fernandez}

A.

* \cite{fernandez}
B.

== end org file ==

Emacs  : GNU Emacs 24.1.50.2 (x86_64-unknown-linux-gnu, GTK+ Version 2.24.10)
 of 2012-06-22 on bill
Package: Org-mode version 7.8.11 (release_7.8.11.139.g9028)

current state:
==============
(setq
 org-export-preprocess-before-selecting-backend-code-hook
'(org-beamer-select-beamer-code)
 org-tab-first-hook '(org-hide-block-toggle-maybe
org-src-native-tab-command-maybe org-babel-hide-result-toggle-maybe)
 org-speed-command-hook '(org-speed-command-default-hook
org-babel-speed-command-hook)
 org-occur-hook '(org-first-headline-recenter)
 org-metaup-hook '(org-babel-load-in-session-maybe)
 org-export-preprocess-before-normalizing-links-hook
'(org-remove-file-link-modifiers)
 org-confirm-shell-link-function 'yes-or-no-p
 org-export-latex-final-hook '(org-beamer-amend-header
org-beamer-fix-toc org-beamer-auto-fragile-frames
                               org-beamer-place-default-actions-for-lists)
 org-export-latex-after-initial-vars-hook '(org-beamer-after-initial-vars)