Remember to cover the basics, that is, what you expected to happen and
what in fact did happen.  You don't know how to make a good report?  See

     http://orgmode.org/manual/Feedback.html#Feedback

Your bug report will be posted to the Org-mode mailing list.
------------------------------------------------------------------------

I created the following simple org file, with a code block in it:
==== BEGIN ====
This is a test.

#+BEGIN_SRC latex :exports none
\newcommand{\test}{Test}
#+END_SRC
==== END ====

Then exported it to LaTeX and had an error (backtrace attached).  The
error always happened regardless of the value of :exports.

Emacs  : GNU Emacs 23.3.50.1 (i386-apple-darwin9.8.0, NS
apple-appkit-949.54)
 of 2011-07-29 on braeburn.aquamacs.org - Aquamacs Distribution 2.3a
Package: Org-mode version 7.7

current state:
==============
(setq
 org-export-latex-after-initial-vars-hook '(org-beamer-after-initial-vars)
 org-speed-command-hook '(org-speed-command-default-hook
              org-babel-speed-command-hook)
 org-blocker-hook '(org-block-todo-from-children-or-siblings-or-parent)
 org-babel-load-languages '((R) (ditaa . t) (dot . t) (emacs-lisp . t)
                (gnuplot . t) (haskell) (latex . t) (matlab . t)
                (ocaml) (python . t) (ruby) (screen) (sh . t) (sql)
                (sqlite))
 org-completion-use-ido t
 org-metaup-hook '(org-babel-load-in-session-maybe)
 org-babel-tangle-lang-exts '(("python" . "py") ("latex" . "tex")
                  ("emacs-lisp" . "el"))
 org-export-blocks-postblock-hook '(org-exp-res/src-name-cleanup)
 org-export-latex-format-toc-function 'org-export-latex-format-toc-default
 org-support-shift-select t
 org-export-preprocess-hook '((lambda nil
                   (org-set-local (quote org-complex-heading-regexp)
                "^\\(\\*+\\)[
 ]+\\(?:\\(TODO\\|NEXT\\|STARTED\\|DONE\\|WAITING\\|CANCELLED\\|DEFERRED\\|PROJECT\\|FINISHED\\)\\>\\)?\\(?:[
    ]*\\(\\[#.\\]\\)\\)?[     ]*\\(.*?\\)\\(?:[
 ]+\\(:[[:alnum:]_@#%:]+:\\)\\)?[     ]*$")
                   )
                  )
 org-tab-first-hook '(org-hide-block-toggle-maybe
org-src-native-tab-command-maybe
              org-babel-hide-result-toggle-maybe)
 org-src-mode-hook '(org-src-babel-configure-edit-buffer
             org-src-mode-configure-edit-buffer)
 org-confirm-shell-link-function 'yes-or-no-p
 org-export-first-hook '(org-beamer-initialize-open-trackers)
 org-babel-pre-tangle-hook '(save-buffer)
 org-cycle-hook '(org-cycle-hide-archived-subtrees org-cycle-hide-drawers
          org-cycle-show-empty-lines
          org-optimize-window-after-visibility-change)
 org-export-preprocess-before-normalizing-links-hook
'(org-remove-file-link-modifiers)
 org-mode-hook '((lambda nil
          (org-add-hook (quote change-major-mode-hook)
           (quote org-babel-show-result-all) (quote append) (quote local))
          )
         (lambda nil
          (org-add-hook (quote change-major-mode-hook)
           (quote org-show-block-all) (quote append) (quote local))
          )
         #[nil "\300\301\302\303\304$\207"
           [org-add-hook change-major-mode-hook org-show-block-all append
            local]
           5]
         #[nil "\300\301\302\303\304$\207"
           [org-add-hook change-major-mode-hook org-babel-show-result-all
            append local]
           5]
         org-babel-result-hide-spec org-babel-hide-all-hashes
         (lambda nil (auto-fill-mode 1)))
 org-ctrl-c-ctrl-c-hook '(org-babel-hash-at-point
org-babel-execute-safely-maybe)
 org-confirm-elisp-link-function 'yes-or-no-p
 org-refile-use-outline-path 'file
 org-export-interblocks '((lob org-babel-exp-lob-one-liners)
              (src org-babel-exp-inline-src-blocks))
 org-enforce-todo-dependencies t
 org-agenda-skip-deadline-if-done t
 org-refile-allow-creating-parent-nodes 'confirm
 org-insert-mode-line-in-empty-file t
 org-occur-hook '(org-first-headline-recenter)
 org-export-preprocess-before-selecting-backend-code-hook
'(org-beamer-select-beamer-code)
 org-agenda-todo-ignore-deadlines t
 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-metadown-hook '(org-babel-pop-to-session-maybe)
 org-export-blocks '((src org-babel-exp-src-block nil)
             (comment org-export-blocks-format-comment t)
             (ditaa org-export-blocks-format-ditaa nil)
             (dot org-export-blocks-format-dot nil))
 )