> Please describe exactly what actions triggered the bug
> and the precise symptoms of the bug:


- Installing emacs 23
- Loading perl-code with errors
- M-x mode-compile

- Effect: The errorlines, filenames and linenumbers are not recognized or
activated in *compilation*

No problem whatsoever with emacs 22 and the same configs!

The problem didn't occure while compiling sh or python files!!!

The problem was reproducible on different machines with Ubuntu 8.04 and 8.10
but not with Windows XP, all with default installation with German
localization.

It was reported NOT to happen with Ubuntu 9.04 on an american machine.

For detailed discussion including a WORKING REGEX-PATCH for mode-compile.el
please look at:

-->
http://groups.google.de/group/gnu.emacs.help/browse_thread/thread/c1a62e304177fefe/9a28488347dd77e7#9a28488347dd77e7

-->
http://groups.google.com/group/emacs-perl-intersection/browse_thread/thread/328823127d1f8b7/8adaceafa79cc216#8adaceafa79cc216

DIAGNOSIS: It seems like the handling of regexes in compile.el changed
considerably from
22 to 23, breaking compatibility with mode-compile.el!!!

A sample perl code to produce 4 error-lines is:
-------------------
use strict;
$a=A;
print $a;
$a=A;
$a=A;
$a=A;
--------------------

> If Emacs crashed ....

No crash!


In GNU Emacs 23.1.50.1 (i686-pc-linux-gnu, GTK+ Version 2.14.4)
 of 2009-10-08 on nc10-ubuntu
Windowing system distributor `The X.Org Foundation', version 11.0.10502000
configured using `configure  '--prefix=/home/lanx/lib/emacs-cvs''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: de_DE.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Perl

Minor modes in effect:
  tooltip-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
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
M-x m o d e - c o m p i l <tab> <return> <return> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <menu-bar> <help-menu>
<send-emacs-bug-report>

Recent messages:
loading debug.el
leaving debug.el
For information about GNU Emacs and the GNU system, type C-h C-a.
Use M-x make-directory RET RET to create the directory and its parents [2
times]
lade mode-compile.el
Loading cl-macs...done
Loading `mode-compile': old-style backquotes detected!
mode-compile: Compiling in Perl mode ... M-x mode-compile-kill to kill.
(No files need saving)
Compilation exited abnormally with code 255

Load-path shadows:
/home/lanx/lib/emacs-cvs/share/emacs/23.1.50/lisp/progmodes/cperl-mode hides
/home/lanx/.emacs.d/debug/cperl-mode