[O] bug in org-element--object-lex seen when exporting (Invalid search bound, wrong side of point)

[Daniel Clemente]

Hi. I describe a rare bug seen in today's org-mode (8.3.6) running in emacs 
26.0.50.1.

1. emacs -Q, and load org-mode
2. Use this file (two lines):

* <<<a>>>
a-bug

3. export to HTML  (C-c C-e h h)

I got:

Debugger entered--Lisp error: (error "Invalid search bound (wrong side of 
point)")
  re-search-forward("\\(?:[_^][-{(*+.,[:alnum:]]\\)\\|[*~=+_/][^        
\n]\\|\\<\\(?:b\\(?:bdb\\|ibtex\\)\\|doi\\|elisp\\|f\\(?:ile\\(?:\\+\\(?:\\(?:emac\\|sy\\)s\\)\\)?\\|tp\\)\\|h\\(?:elp\\|ttps?\\)\\|i\\(?:d\\|nfo\\|rc\\)\\|m\\(?:ailto\\|essage\\)\\|news\\|shell\\|tel\\|w\\(?:3m\\|l\\)\\):\\|\\[\\(?:fn:\\|\\[\\|[0-9]\\{4\\}-[0-9]\\{2\\}-[0-9]\\{2\\}\\|[0-9]*\\(?:%\\|/[0-9]*\\)\\]\\)\\|@@\\|{{{\\|<\\(?:%%\\|<\\|[0-9]\\|\\(?:b\\(?:bdb\\|ibtex\\)\\|doi\\|elisp\\|f\\(?:ile\\(?:\\+\\(?:\\(?:emac\\|sy\\)s\\)\\)?\\|tp\\)\\|h\\(?:elp\\|ttps?\\)\\|i\\(?:d\\|nfo\\|rc\\)\\|m\\(?:ailto\\|essage\\)\\|news\\|shell\\|tel\\|w\\(?:3m\\|l\\)\\)\\)\\|\\$\\|\\\\\\(?:[a-zA-Z[(]\\|\\\\[
   ]*$\\|_ +\\)\\|\\(?:call\\|src\\)_" 13 t)
  org-element--object-lex((bold code entity export-snippet footnote-reference 
inline-babel-call inline-src-block italic line-break latex-fragment link macro 
radio-target statistics-cookie strike-through subscript superscript target 
timestamp underline verbatim))
  org-element--parse-objects(13 19 (paragraph (:begin 13 :end 19 
:contents-begin 13 :contents-end 19 :post-blank 0 :post-affiliated 13)) (bold 
code entity export-snippet footnote-reference inline-babel-call 
inline-src-block italic line-break latex-fragment link macro radio-target 
statistics-cookie strike-through subscript superscript target timestamp 
underline verbatim))
  org-element--parse-elements(13 19 planning nil nil nil (section (:begin 13 
:end 19 :contents-begin 13 :contents-end 19 :post-blank 0 :post-affiliated 13)))
  org-element--parse-elements(13 19 section nil nil nil (headline (:raw-value 
"<<<a>>>" :begin 2 :end 19 :pre-blank 1 :contents-begin 13 :contents-end 19 
:level 1 :priority nil :tags nil :todo-keyword nil :todo-type nil :post-blank 0 
:footnote-section-p nil :archivedp nil :commentedp nil :post-affiliated 2 
:title ((radio-target (:begin 4 :end 11 :contents-begin 7 :contents-end 8 
:post-blank 0 :value "a" :parent #0) #("a" 0 1 (:parent #3)))))))
  org-element--parse-elements(2 19 first-section nil nil nil (org-data nil))
  org-element-parse-buffer(nil nil)
  …



It happens with one-letter radios. I found it because I had <<<R>>> and r-cran 
in the same file.

Greetings,

Daniel