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 mailing list.
------------------------------------------------------------------------

After update to org 9.0, the source code block can't no longer be exported
and
org alerts an error.

The minimal config I use is

(package-initialize)

(setq debug-on-error t
      debug-on-signal nil
      debug-on-quit nil)

(require 'org)

where the org is installed by elpa.

The test.org file contains

#+BEGIN_SRC latex :results drawer :exports results
  \begin{eqnarray}
    a + b = c \label{eq1}
  \end{eqnarray}
#+END_SRC

ONLY. Running C-c C-e l l gives error

Debugger entered--Lisp error: (wrong-type-argument stringp nil)
  org-babel-exp-src-block()
  org-babel-exp-process-buffer()
  org-export-as(latex nil nil nil (:output-file "./test.tex"))
  org-export-to-file(latex "./test.tex" nil nil nil nil nil)
  org-latex-export-to-latex(nil nil nil nil)
  org-export-dispatch(nil)
  funcall-interactively(org-export-dispatch nil)
  call-interactively(org-export-dispatch nil nil)
  command-execute(org-export-dispatch)


Emacs  : GNU Emacs 25.1.1 (x86_64-apple-darwin16.1.0, Carbon Version 157
AppKit 1504.6)
 of 2016-11-02
Package: Org mode version 9.0.1 (9.0.1-elpa @
/Users/Yomisuko/.emacs.d/elpa/org-20161118/)

current state:
==============
(setq
 org-tab-first-hook '(org-babel-hide-result-toggle-maybe
org-babel-header-arg-expand)
 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-html-format-drawer-function #[514 "\207" [] 3 "\n\n(fn NAME CONTENTS)"]
 org-latex-format-inlinetask-function
'org-latex-format-inlinetask-default-function
 org-confirm-shell-link-function 'yes-or-no-p
 org-ascii-format-inlinetask-function 'org-ascii-format-inlinetask-default
 org-latex-format-headline-function
'org-latex-format-headline-default-function
 org-after-todo-state-change-hook '(org-clock-out-if-current)
 org-latex-format-drawer-function #[514 "\207" [] 3 "\n\n(fn _ CONTENTS)"]
 org-odt-format-headline-function 'org-odt-format-headline-default-function
 org-src-mode-hook '(org-src-babel-configure-edit-buffer
    org-src-mode-configure-edit-buffer)
 org-agenda-before-write-hook '(org-agenda-add-entry-text)
 org-babel-pre-tangle-hook '(save-buffer)
 org-mode-hook '(#[0 "\300\301\302\303\304$\207"
  [add-hook change-major-mode-hook org-show-block-all append local]
  5]
#[0 "\300\301\302\303\304$\207"
  [add-hook change-major-mode-hook org-babel-show-result-all append
   local]
  5]
org-babel-result-hide-spec org-babel-hide-all-hashes)
 org-archive-hook '(org-attach-archive-delete-maybe)
 org-ascii-format-drawer-function #[771 " \207" [] 4 "\n\n(fn NAME CONTENTS
WIDTH)"]
 org-odt-format-inlinetask-function
'org-odt-format-inlinetask-default-function
 org-cycle-hook '(org-cycle-hide-archived-subtrees org-cycle-hide-drawers
 org-cycle-show-empty-lines
 org-optimize-window-after-visibility-change)
 org-confirm-elisp-link-function 'yes-or-no-p
 org-metadown-hook '(org-babel-pop-to-session-maybe)
 org-odt-format-drawer-function #[514 "\207" [] 3 "\n\n(fn NAME CONTENTS)"]
 org-html-format-headline-function
'org-html-format-headline-default-function
 org-link-parameters '(("id" :follow org-id-open)
      ("rmail" :follow org-rmail-open :store org-rmail-store-link)
      ("mhe" :follow org-mhe-open :store org-mhe-store-link)
      ("irc" :follow org-irc-visit :store org-irc-store-link)
      ("info" :follow org-info-open :export org-info-export :store
org-info-store-link)
      ("gnus" :follow org-gnus-open :store org-gnus-store-link)
      ("docview" :follow org-docview-open :export org-docview-export
:store org-docview-store-link)
      ("bibtex" :follow org-bibtex-open :store org-bibtex-store-link)
      ("bbdb" :follow org-bbdb-open :export org-bbdb-export
:complete org-bbdb-complete-link :store org-bbdb-store-link)
      ("w3m" :store org-w3m-store-link) ("file+sys") ("file+emacs")
      ("doi" :follow org--open-doi-link)
      ("elisp" :follow org--open-elisp-link)
      ("file" :complete org-file-complete-link)
      ("ftp" :follow
(lambda (path) (browse-url (concat "ftp:" path))))
      ("help" :follow org--open-help-link)
      ("http" :follow
(lambda (path) (browse-url (concat "http:" path))))
      ("https" :follow
(lambda (path) (browse-url (concat "https:" path))))
      ("mailto" :follow
(lambda (path) (browse-url (concat "mailto:" path))))
      ("message" :follow
(lambda (path) (browse-url (concat "message:" path))))
      ("news" :follow
(lambda (path) (browse-url (concat "news:" path))))
      ("shell" :follow org--open-shell-link))
 org-html-format-inlinetask-function
'org-html-format-inlinetask-default-function
 org-clock-out-hook '(org-clock-remove-empty-clock-drawer)
 )