bug#66161: 30.0.50; cperl-mode bug in fontification after __END__

[Mauro Aranda <maurooaranda@gmail.com>]

emacs -Q
C-x C-f bug.pl
M-x cperl-mode

Enter the following:
#!/usr/bin/perl

use strict;
use warnings;

print("Hello World\n");

__END__

TODO:
What's happening?

It's all messed up.


Fontificacion after __END__ is wrong.


In GNU Emacs 30.0.50 (build 9, x86_64-pc-linux-gnu, GTK+ Version
  3.24.33, cairo version 1.16.0) of 2023-09-21 built on tbb-desktop
Repository revision: 9db3fbd369121ddd34e7f4febe8688d758a5dbb7
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12201001
System Description: Ubuntu 22.04.2 LTS

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GPM GSETTINGS HARFBUZZ JPEG
JSON LCMS2 LIBOTF LIBSELINUX LIBSYSTEMD LIBXML2 M17N_FLT MODULES NOTIFY
INOTIFY PDUMPER PNG RSVG SECCOMP SOUND SQLITE3 THREADS TIFF
TOOLKIT_SCROLL_BARS TREE_SITTER X11 XDBE XIM XINPUT2 XPM GTK3 ZLIB

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

Major mode: CPerl

Minor modes in effect:
   tooltip-mode: t
   global-eldoc-mode: t
   show-paren-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
   minibuffer-regexp-mode: t
   line-number-mode: t
   indent-tabs-mode: t
   transient-mark-mode: t
   auto-composition-mode: t
   auto-encryption-mode: t
   auto-compression-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message mailcap yank-media puny dired
dired-loaddefs rfc822 mml mml-sec password-cache epa derived epg rfc6068
epg-config gnus-util text-property-search mm-decode mm-bodies mm-encode
mail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail rfc2047
rfc2045 ietf-drums mm-util mail-prsvr mail-utils time-date subr-x
cl-loaddefs cl-lib cperl-mode rx facemenu perl-mode rmc iso-transl
tooltip cconv eldoc paren electric uniquify ediff-hook vc-hooks
lisp-float-type elisp-mode mwheel term/x-win x-win term/common-win x-dnd
touch-screen tool-bar dnd fontset image regexp-opt fringe tabulated-list
replace newcomment text-mode lisp-mode prog-mode register page tab-bar
menu-bar rfn-eshadow isearch easymenu timer select scroll-bar mouse
jit-lock font-lock syntax font-core term/tty-colors frame minibuffer
nadvice seq simple cl-generic indonesian philippine 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 emoji-zwj charscript charprop
case-table epa-hook jka-cmpr-hook help abbrev obarray oclosure
cl-preloaded button loaddefs theme-loaddefs faces cus-face macroexp
files window text-properties overlay sha1 md5 base64 format env
code-pages mule custom widget keymap hashtable-print-readable backquote
threads dbusbind inotify lcms2 dynamic-setting system-font-setting
font-render-setting cairo gtk x-toolkit xinput2 x multi-tty move-toolbar
make-network-process emacs)

Memory information:
((conses 16 46308 13707) (symbols 48 6033 0) (strings 32 15859 1563)
  (string-bytes 1 467838) (vectors 16 11446)
  (vector-slots 8 175135 12716) (floats 8 24 32) (intervals 56 361 17)
  (buffers 992 12))