bug#34823: 27.0.50; re-search-forward infloop

[Vitalie Spinu]

Hi,

In the context of markdown-mode I am seeing a font-lock infloop with a
relatively simple regexp:

 1) emacs -Q
 2) open a buffer with the following line

   "$_\t$tmp\t$cat\t$donor\t$stage\t$pool\t$rep\t$time\t$comment"'

 3) at bol eval (re-search-forward "\\(\\w[^\n]*\\)+}")
    which infloops

I see it with emacs 25, 26 and 27.0.5.

  Vitalie

----

In GNU Emacs 27.0.50 (build 7, x86_64-pc-linux-gnu, GTK+ Version 3.22.30)
 of 2018-08-31 built on Galago
Repository revision: 244b6827257fb0ec9c14f19b9dd01a0e1bee1d75
Windowing system distributor 'The X.Org Foundation', version 11.0.11906000
System Description: Ubuntu 18.04.1 LTS

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
(New file)
Mark set
Quit [2 times]
Mark activated [4 times]
ido-read-internal: Command attempted to use minibuffer while in minibuffer
Quit [3 times]
ido-read-internal: Command attempted to use minibuffer while in minibuffer
Quit [2 times]
ad-Advice-delete-char: Text is read-only [3 times]

Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK SOUND GPM DBUS GSETTINGS NOTIFY
ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB
TOOLKIT_SCROLL_BARS GTK3 X11 THREADS LCMS2

Important settings:
  value of $LC_MONETARY: nl_NL.UTF-8
  value of $LC_NUMERIC: nl_NL.UTF-8
  value of $LC_TIME: en_DK.UTF-8
  value of $LANG: en_GB.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Fundamental

Minor modes in effect:
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  helm-cider-mode: t
  global-eclim-mode: t
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  helm-descbinds-mode: t
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  pdf-occur-global-minor-mode: t
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  save-place-mode: t
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  savehist-mode: t
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  beacon-mode: t
  override-global-mode: t
  global-subword-mode: t
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  ido-everywhere: t
  cl-old-struct-compat-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-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
  size-indication-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
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hides ~/dev/math-symbol-lists/math-symbol-lists
/home/vspinu/Dropbox/ELPA/math-symbol-lists-20170221.1353/msl-build hides 
~/dev/math-symbol-lists/msl-build
/home/vspinu/Dropbox/ELPA/key-combo-20150324.1439/key-combo hides 
~/dev/key-combo/key-combo
/home/vspinu/Dropbox/ELPA/company-math-20171016.1514/company-math hides 
~/VC/company-math/company-math
/home/vspinu/Dropbox/ELPA/smartparens-20181007.1501/smartparens hides 
~/VC/smartparens/smartparens
/home/vspinu/Dropbox/ELPA/smartparens-20181007.1501/smartparens-html hides 
~/VC/smartparens/smartparens-html
/home/vspinu/Dropbox/ELPA/smartparens-20181007.1501/smartparens-lua hides 
~/VC/smartparens/smartparens-lua
/home/vspinu/Dropbox/ELPA/smartparens-20181007.1501/smartparens-scala hides 
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/home/vspinu/Dropbox/ELPA/smartparens-20181007.1501/smartparens-clojure hides 
~/VC/smartparens/smartparens-clojure
/home/vspinu/Dropbox/ELPA/smartparens-20181007.1501/smartparens-config hides 
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/home/vspinu/Dropbox/ELPA/smartparens-20181007.1501/smartparens-ruby hides 
~/VC/smartparens/smartparens-ruby
/home/vspinu/Dropbox/ELPA/smartparens-20181007.1501/smartparens-rust hides 
~/VC/smartparens/smartparens-rust
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~/VC/smartparens/smartparens-racket
/home/vspinu/Dropbox/ELPA/smartparens-20181007.1501/smartparens-haskell hides 
~/VC/smartparens/smartparens-haskell
/home/vspinu/Dropbox/ELPA/smartparens-20181007.1501/smartparens-latex hides 
~/VC/smartparens/smartparens-latex
/home/vspinu/Dropbox/ELPA/smartparens-20181007.1501/smartparens-pkg hides 
~/VC/smartparens/smartparens-pkg
/home/vspinu/Dropbox/ELPA/spinner-1.7.3/spinner hides ~/VC/spinner.el/spinner
/home/vspinu/Dropbox/ELPA/epl-20180205.2049/epl hides ~/VC/epl/epl
/home/vspinu/Dropbox/ELPA/dash-20180903.1042/dash hides ~/VC/dash.el/dash
/home/vspinu/Dropbox/ELPA/pkg-info-20150517.1143/pkg-info hides 
~/VC/pkg-info.el/pkg-info
/home/vspinu/Dropbox/ELPA/projectile-20180824.2239/projectile hides 
~/VC/projectile/projectile
/home/vspinu/Dropbox/ELPA/auto-complete-20170125.245/auto-complete-pkg hides 
~/VC/auto-complete/auto-complete-pkg
/home/vspinu/Dropbox/ELPA/auto-complete-20170125.245/auto-complete-config hides 
~/VC/auto-complete/auto-complete-config
/home/vspinu/Dropbox/ELPA/auto-complete-20170125.245/auto-complete hides 
~/VC/auto-complete/auto-complete
/home/vspinu/Dropbox/ELPA/color-theme-solarized-20171024.1525/solarized-theme 
hides ~/VC/solarized-emacs/solarized-theme
/home/vspinu/Dropbox/ELPA/queue-0.2/queue hides ~/Dropbox/.emacs.d/queue
~/VC/markdown-mode/markdown-mode hides ~/Dropbox/.emacs.d/markdown-mode
/home/vspinu/Dropbox/ELPA/rebox2-20121113.2100/rebox2 hides 
~/Dropbox/.emacs.d/rebox2
~/Dropbox/.emacs.d/allout-widgets hides 
/home/vspinu/bin/emacs/lisp/allout-widgets
~/Dropbox/.emacs.d/allout hides /home/vspinu/bin/emacs/lisp/allout
/home/vspinu/Dropbox/ELPA/less-css-mode-20161001.453/less-css-mode hides 
/home/vspinu/bin/emacs/lisp/textmodes/less-css-mode
~/Dropbox/.emacs.d/org-protocol hides 
/home/vspinu/bin/emacs/lisp/org/org-protocol
~/Dropbox/.emacs.d/tabulated-list hides 
/home/vspinu/bin/emacs/lisp/emacs-lisp/tabulated-list

Features:
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Memory information:
((conses 16 972819 26432)
 (symbols 48 68247 1)
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 (strings 32 246201 16927)
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