Subject: bug#65726: closed (Re: bug#65726: 29.1.50; Crash in regexp engine)

From: [email-masked] (GNU bug Tracking System)
Date: Mon, 04 Sep 2023 17:13:02 +0000

Your bug report

#65726: 29.1.50; Crash in regexp engine

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
65726: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=65726
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#65726: 29.1.50; Crash in regexp engine
From: Stefan Monnier <[email-masked]>
To: Eli Zaretskii <[email-masked]>
Cc: [email-masked], [email-masked]
Date: Mon, 04 Sep 2023 13:12:20 -0400
List-Id: <debbugs-submit.debbugs.gnu.org>

> Yes, with this patch the problem is gone.

Thanks, pushed to `emacs-29`.

        Stefan

Subject: 29.1.50; Crash in regexp engine
From: martin rudalics <[email-masked]>
To: Bug-Gnu-Emacs <[email-masked]>
Date: Mon, 4 Sep 2023 09:46:24 +0200
List-Id: <debbugs-submit.debbugs.gnu.org>

With emacs -Q load the attached file elinfo.el.  Now type

C-h S split-window RET

C-x o

C-c C-g

This crashes Emacs here with

Thread 1 "emacs" received signal SIGSEGV, Segmentation fault.
0x000000000068810a in skip_noops (p=<error reading variable: Cannot access memory at address 0x7fffff66fff8>, pend=<error reading variable: Cannot access memory at address 0x7fffff66fff0>) at ../../src/regex-emacs.c:3556
3556	{

and an infinite backtrace starting with

Python Exception <class 'gdb.MemoryError'> Cannot access memory at address 0x7fffff66fff8:
#0  0x000000000068810a in skip_noops (p=#1  0x0000000000688823 in mutually_exclusive_p (bufp=0xec9c30 <searchbufs+752>, p1=0x1fcee74 "\004\005", p2=0x1fcee81 "\016\063") at ../../src/regex-emacs.c:3665
#2  0x0000000000688e19 in mutually_exclusive_p (bufp=0xec9c30 <searchbufs+752>, p1=0x1fcee74 "\004\005", p2=0x1fcee81 "\016\063") at ../../src/regex-emacs.c:3838
#3  0x0000000000688e3c in mutually_exclusive_p (bufp=0xec9c30 <searchbufs+752>, p1=0x1fcee74 "\004\005", p2=0x1fceeba "\004\020") at ../../src/regex-emacs.c:3839
#4  0x0000000000688e3c in mutually_exclusive_p (bufp=0xec9c30 <searchbufs+752>, p1=0x1fcee74 "\004\005", p2=0x1fcee84 "\002\001@\004\020") at ../../src/regex-emacs.c:3839
#5  0x0000000000688e19 in mutually_exclusive_p (bufp=0xec9c30 <searchbufs+752>, p1=0x1fcee74 "\004\005", p2=0x1fcee81 "\016\063") at ../../src/regex-emacs.c:3838
...

The same scenario worked well with Emacs 22 through 28.

martin

In GNU Emacs 29.1.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.5,
  cairo version 1.16.0) of 2023-09-03 built on restno
Repository revision: f1e4cbe72aa4da9351cbbcd209d9233c68dd9fbb
Repository branch: emacs-29
Windowing system distributor 'The X.Org Foundation', version 11.0.12004000
System Description: Debian GNU/Linux 10 (buster)

Configured using:
  'configure --with-gif=ifavailable --with-tiff=ifavailable
  --with-gnutls=no --without-pop --enable-gcc-warnings=warn-only
  --enable-checking=yes,glyphs --enable-check-lisp-object-type=yes
  'CFLAGS=-O0 -g3 -no-pie -Wno-missing-braces''

Configured features:
CAIRO DBUS FREETYPE GIF GLIB GSETTINGS HARFBUZZ JPEG LIBSELINUX MODULES
NOTIFY INOTIFY PDUMPER PNG SECCOMP SOUND THREADS TOOLKIT_SCROLL_BARS X11
XDBE XIM XINPUT2 XPM GTK3 ZLIB

Important settings:
   value of $LANG: de_AT.utf8
   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
   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
   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 time-date subr-x mm-decode
mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader
cl-loaddefs cl-lib sendmail rfc2047 rfc2045 ietf-drums mm-util
mail-prsvr mail-utils elinfo texinfo texinfo-loaddefs info 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 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 dynamic-setting system-font-setting
font-render-setting cairo move-toolbar gtk x-toolkit xinput2 x multi-tty
make-network-process emacs)

Memory information:
((conses 16 45758 8352)
  (symbols 48 5682 0)
  (strings 32 15622 2110)
  (string-bytes 1 431024)
  (vectors 16 10081)
  (vector-slots 8 157669 13073)
  (floats 8 26 23)
  (intervals 56 218 0)
  (buffers 976 10))