Hello,

Trying to edebug org-export-data in emacs -Q (emacs 26.0.91, using inbuilt
Org 9.1.6) gives this error:

edebug-syntax-error: Invalid read syntax: "Failed matching", (&rest
(&define name (&rest arg) cl-declarations-or-string def-body))

Here is the full backtrace:
https://gist.githubusercontent.com/kaushalmodi/680ae8d5b1960ae88b487a9e13fe49d7/raw/684844ed59ea891900d5f227e3f92444c93537e1/*scratch-fundamental-mode*.txt

Steps to recreate:

1. emacs -Q
2. M-x org-mode (so that org-export-data gets loaded)
3. C-h f org-export-data
4. Navigate to the source from the link in help buffer.
5. C-u C-M-x inside the org-export-data defun
6. You get this error.

In GNU Emacs 26.0.91 (build 4, x86_64-pc-linux-gnu, GTK+ Version 2.24.23)
 of 2018-01-31
Repository revision: 56c37bbdb60f201791b57a3af2f47b7517de810c
Windowing system distributor 'The X.Org Foundation', version 11.0.60900000
System Description:    Red Hat Enterprise Linux Workstation release 6.6
(Santiago)

Recent messages:
Quit
Type C-x 1 to delete the help window.
uncompressing ox.el.gz...done
edebug-syntax-error: Invalid read syntax: "Failed matching", (&rest
(&define name (&rest arg) cl-declarations-or-string def-body))
Debug on Error enabled globally
Entering debugger...
Mark set [2 times]
Saved text until " nil nil)
  command-execute(eval-defun)
"

Configured using:
 'configure --with-modules
 --prefix=/home/kmodi/usr_local/apps/6/emacs/emacs-26
 '--program-transform-name=s/^ctags$/ctags_emacs/'
 --enable-checking=yes,glyphs --enable-check-lisp-object-type
 'CPPFLAGS=-I/home/kmodi/usr_local/6/include -I/usr/include/freetype2
 -I/usr/include' 'CFLAGS=-ggdb3 -O0' 'CXXFLAGS=-ggdb3 -O0'
 'LDFLAGS=-L/home/kmodi/usr_local/6/lib -L/home/kmodi/usr_local/6/lib64
 -ggdb3''

Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK SOUND GPM DBUS GSETTINGS NOTIFY
ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE LIBOTF XFT ZLIB
TOOLKIT_SCROLL_BARS GTK2 X11 MODULES THREADS

Important settings:
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: @im=none
  locale-coding-system: utf-8-unix

Major mode: Debugger

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  buffer-read-only: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug sendmail cl-print debug cus-start
cus-load cl-macs edebug org-table ob-ditaa ob-plantuml org-archive
org-capture org-clock org-colview org-crypt org-habit org-agenda
org-indent ox-odt rng-loc rng-uri rng-parse rng-match rng-dt rng-util
rng-pttrn nxml-parse nxml-ns nxml-enc xmltok nxml-util ox-latex
ox-icalendar ox-html table ox-ascii ox-publish ox thingatpt help-fns
radix-tree help-mode org-rmail org-mhe org-irc org-info org-gnus nnir
gnus-sum gnus-group gnus-undo gnus-start gnus-cloud nnimap nnmail
mail-source tls gnutls utf7 netrc nnoo parse-time gnus-spec gnus-int
gnus-range message rmc puny seq byte-opt gv bytecomp byte-compile cconv
rfc822 mml mml-sec password-cache epa derived epg epg-config mm-decode
mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader
gnus-win gnus nnheader gnus-util rmail rmail-loaddefs rfc2047 rfc2045
ietf-drums mail-utils mm-util mail-prsvr wid-edit org-docview doc-view
jka-compr image-mode dired dired-loaddefs org-bibtex bibtex org-bbdb
org-w3m org-element cl-seq avl-tree generator org advice org-macro
org-footnote org-pcomplete pcomplete org-list org-faces org-entities
noutline outline easy-mmode org-version ob-emacs-lisp ob ob-tangle
org-src ob-ref ob-lob ob-table ob-keys ob-exp ob-comint comint
ansi-color ring ob-core ob-eval org-compat org-macs org-loaddefs
format-spec find-func cal-menu easymenu calendar cal-loaddefs
cl-loaddefs cl-lib elec-pair time-date mule-util tooltip eldoc electric
uniquify ediff-hook vc-hooks lisp-float-type mwheel term/x-win x-win
term/common-win x-dnd tool-bar dnd fontset image regexp-opt fringe
tabulated-list replace newcomment text-mode elisp-mode lisp-mode
prog-mode register page menu-bar rfn-eshadow isearch timer select
scroll-bar mouse jit-lock font-lock syntax facemenu font-core
term/tty-colors frame cl-generic cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms cp51932
hebrew greek romanian slovak czech european ethiopic indian cyrillic
chinese composite charscript charprop case-table epa-hook jka-cmpr-hook
help simple abbrev obarray minibuffer cl-preloaded nadvice loaddefs
button faces cus-face macroexp files text-properties overlay sha1 md5
base64 format env code-pages mule custom widget hashtable-print-readable
backquote dbusbind inotify dynamic-setting system-font-setting
font-render-setting move-toolbar gtk x-toolkit x multi-tty
make-network-process emacs)

Memory information:
((conses 16 243982 32885)
 (symbols 48 36144 1)
 (miscs 40 119 117)
 (strings 32 83426 1452)
 (string-bytes 1 3382615)
 (vectors 16 34810)
 (vector-slots 8 710050 5482)
 (floats 8 240 123)
 (intervals 56 408467 38)
 (buffers 992 14)
 (heap 1024 74243 1906))

-- 

Kaushal Modi