start with emacs -Q;
in *scratch* buffer, go to top and C-s for something
While in isearch mode, press M-%

Insead of asking for replace string, the message buffer says "Wrong type
argument: arrayp, nil"




In GNU Emacs 25.0.92.8 (x86_64-unknown-linux-gnu, GTK+ Version 3.10.8)
 of 2016-03-21 built on zhyang.mtv.corp.google.com
Repository revision: 76ef52267cf887e3e1aa6d25b3b16dd0601dd459
Windowing system distributor 'The X.Org Foundation', version 11.0.11501000
System Description: Ubuntu 14.04 LTS

Configured features:
XPM JPEG TIFF GIF PNG RSVG SOUND GSETTINGS NOTIFY GNUTLS FREETYPE LIBOTF
XFT ZLIB TOOLKIT_SCROLL_BARS GTK3 X11

Important settings:
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: @im=ibus
  locale-coding-system: utf-8-unix

Major mode: Lisp Interaction

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
  line-number-mode: t
  transient-mark-mode: t

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Quit [3 times]
isearch--describe-regexp-mode: Wrong type argument: arrayp, nil

Load-path shadows:
None found.

Features:
(shadow sort mail-extr misearch multi-isearch emacsbug message dired
format-spec rfc822 mml mml-sec password-cache epg epg-config gnus-util
mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils
mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util help-fns
help-mode easymenu cl-loaddefs pcase cl-lib mail-prsvr mail-utils
time-date mule-util tooltip eldoc electric uniquify ediff-hook vc-hooks
lisp-float-type mwheel x-win term/common-win x-dnd tool-bar dnd fontset
image regexp-opt fringe tabulated-list newcomment elisp-mode lisp-mode
prog-mode register page menu-bar rfn-eshadow timer select scroll-bar
mouse jit-lock font-lock syntax facemenu font-core 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 charscript case-table epa-hook
jka-cmpr-hook help simple abbrev 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 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 90349 12324)
 (symbols 48 20035 0)
 (miscs 40 526 196)
 (strings 32 15185 4779)
 (string-bytes 1 452841)
 (vectors 16 12993)
 (vector-slots 8 450841 5135)
 (floats 8 165 85)
 (intervals 56 192 4)
 (buffers 976 11)
 (heap 1024 44170 991))