bug#36946: 26.2; cperl-mode indent bug

[Hiroshi Fujishima]

{
  $x = $y[$i]++ / 1;
$z <----- indent does not work well.


In GNU Emacs 26.2 (build 1, amd64-portbld-freebsd11.2, GTK+ Version 3.24.9)
Windowing system distributor 'The Cygwin/X Project', version 11.0.12002000
Recent messages:
spam-split: calling the spam-check-bogofilter-headers function
Wrote /home/hirobo/Mail/cloud-emergency-ml/1509879
spam-split: calling the spam-check-bogofilter-headers function
Wrote /home/hirobo/Mail/enternoc/155320
nnml: Reading incoming mail (701 new)...done
Reading active file via nnml...done
Reading active file via nndraft...done
Checking new news...done
Couldn’t find end of charclass in a REx, pos=2474 [2 times]
Making completion list...

Configured using:
 'configure --disable-build-details --localstatedir=/var
 --without-gpm --with-x --enable-acl --without-cairo --with-dbus
 --with-gconf --with-gif --with-gnutls --with-gsettings
 --with-x-toolkit=gtk3 --with-jpeg --with-json
 --with-file-notification=kqueue --with-lcms2 --with-m17n-flt
 --with-imagemagick --with-mailutils --with-modules
 --with-sound=oss --with-libotf --with-png
 --with-toolkit-scroll-bars --with-rsvg --with-threads
 --with-tiff --with-xft --with-xim --with-xml2 --with-xpm
 --without-xwidgets --x-libraries=/usr/local/lib
 --x-includes=/usr/local/include --prefix=/usr/local
 --mandir=/usr/local/man --disable-silent-rules
 --infodir=/usr/local/share/emacs/info/
 --build=amd64-portbld-freebsd11.2 'CFLAGS=-O2 -pipe
 -fstack-protector-strong -isystem /usr/local/include
 -fno-strict-aliasing ' 'CPPFLAGS=-isystem /usr/local/include'
 'LDFLAGS= -fstack-protector-strong -L/usr/local/lib ''

Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK SOUND DBUS GCONF GSETTINGS
GLIB NOTIFY ACL GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB
TOOLKIT_SCROLL_BARS GTK3 X11 XDBE XIM MODULES THREADS LCMS2

Important settings:
  value of $LC_CTYPE: ja_JP.UTF-8
  locale-coding-system: utf-8-unix

Major mode: CPerl

Minor modes in effect:
  diff-auto-refine-mode: t
  iswitchb-mode: t
  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
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort gnus-cite ecomplete mail-extr nnir emacsbug vc-git
diff-mode cperl-mode gnus-topic cursor-sensor qp nndraft nnmh
nnml gnus-agent gnus-srvr gnus-score score-mode nnvirtual nntp
gnus-cache bbdb-message sendmail bbdb-gnus bbdb-mua gnus-est
gnus-mlspl spam spam-stat bbdb-com crm bbdb bbdb-site timezone
gnus-uu yenc gnus-msg gnus-art mm-uu mml2015 mm-view mml-smime
smime dig mailcap 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 dired
dired-loaddefs format-spec rfc822 mml mml-sec epa derived epg
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 elec-pair ccc w3m-load migemo minibuf-isearch
easy-mmode session iswitchb ffap thingatpt mic-paren cp5022x
finder-inf info package easymenu epg-config url-handlers
url-parse auth-source cl-seq eieio eieio-core cl-macs
eieio-loaddefs password-cache url-vars seq byte-opt gv bytecomp
byte-compile cconv cl-loaddefs cl-lib time-date mule-util advice
japan-util skk-setup skk-autoloads 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 threads dbusbind kqueue lcms2 dynamic-setting
system-font-setting font-render-setting move-toolbar gtk
x-toolkit x multi-tty make-network-process emacs)

Memory information:
((conses 16 352429 36623)
 (symbols 48 38103 1)
 (miscs 40 76 258)
 (strings 32 107764 9478)
 (string-bytes 1 2999933)
 (vectors 16 34542)
 (vector-slots 8 840386 23980)
 (floats 8 788 15)
 (intervals 56 930 0)
 (buffers 992 19))