Subject: 30.0.93; Crash when copy-sequence on clear-string'ed multibyte strings with text properties
From: Kanakana <[email-masked]>
To: [email-masked]
Date: Wed, 15 Jan 2025 18:48:30 +0800
List-Id: <debbugs-submit.debbugs.gnu.org>

** Reproducing Steps

Run:

     emacs -Q --batch --eval '(let ((s #("🤗" 0 1 (prop value)))) 
(clear-string s) (copy-sequence s))'

** Expected Behavior

I don't know. Are text properties expected to handle string length
change via clear-string?

** Observed Symptoms

Emacs crashes, with stack trace saying:

#+begin_verse
#0 0x00005555557e2a58 in copy_intervals ()
#1 0x000055555576dfc4 in Fcopy_sequence ()
#2 0x0000555555765c65 in eval_sub ()
#3 0x0000555555769080 in Flet ()
#4 0x0000555555765b0a in eval_sub ()
#5 0x0000555555766353 in Feval ()
#6 0x0000555555766eee in Ffuncall ()
#7 0x00007fffeed925b6 in F636f6d6d616e642d6c696e652d31_command_line_1_0 ()
from 
/usr/bin/../lib/emacs/30.0.93/native-lisp/30.0.93-3fae9fb4/preloaded/startup-bbc6ea72-bc20aae4.eln
#8 0x0000555555766eee in Ffuncall ()
#9 0x00007fffeed890a7 in F636f6d6d616e642d6c696e65_command_line_0 ()
from 
/usr/bin/../lib/emacs/30.0.93/native-lisp/30.0.93-3fae9fb4/preloaded/startup-bbc6ea72-bc20aae4.eln
#10 0x0000555555766eee in Ffuncall ()
#11 0x00007fffeed85500 in 
F6e6f726d616c2d746f702d6c6576656c_normal_top_level_0 ()
from 
/usr/bin/../lib/emacs/30.0.93/native-lisp/30.0.93-3fae9fb4/preloaded/startup-bbc6ea72-bc20aae4.eln
#12 0x0000555555765aff in eval_sub ()
#13 0x0000555555766353 in Feval ()
#14 0x00005555556cbe3e in top_level_2 ()
#15 0x0000555555762127 in internal_condition_case ()
#16 0x00005555556cc97b in top_level_1 ()
#17 0x000055555576206a in internal_catch ()
#18 0x00005555556cbd46 in command_loop ()
#19 0x00005555556d3cad in recursive_edit_1 ()
#20 0x00005555556d4066 in Frecursive_edit ()
#21 0x00005555555e2428 in main ()
#+end_verse

(Also reproduced in an Emacs 29.1 AppImage from
https://github.com/blahgeek/emacs-appimage/releases/20240102-1200 .)

In GNU Emacs 30.0.93 (build 2, x86_64-pc-linux-gnu, GTK+ Version
3.24.43, cairo version 1.18.2) of 2025-01-15 built on lil-end
Repository revision: b981889e9ee0a37f1bc8e2c9b90a5d154c1d032e
Repository branch: makepkg
System Description: EndeavourOS

Configured using:
'configure --prefix=/usr --sysconfdir=/etc --libexecdir=/usr/lib
--localstatedir=/var --mandir=/usr/share/man --with-gameuser=:games
--with-modules --without-m17n-flt --without-gconf
--with-native-compilation=yes --with-xinput2 --with-pgtk
--without-xaw3d --with-sound=no --with-tree-sitter --without-gpm
--without-compress-install
'--program-transform-name=s/\([ec]tags\)/\1.emacs/'
'CFLAGS=-march=x86-64 -mtune=generic -O2 -pipe -fno-plt -fexceptions
-Wp,-D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security
-fstack-clash-protection -fcf-protection'
LDFLAGS=-Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now
'CXXFLAGS=-march=x86-64 -mtune=generic -O2 -pipe -fno-plt -fexceptions
-Wp,-D_FORTIFY_SOURCE=2 -Wformat -Werror=format-security
-fstack-clash-protection -fcf-protection -Wp,-D_GLIBCXX_ASSERTIONS''

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG
LCMS2 LIBOTF LIBSYSTEMD LIBXML2 MODULES NATIVE_COMP NOTIFY INOTIFY
PDUMPER PGTK PNG RSVG SECCOMP SQLITE3 THREADS TIFF TOOLKIT_SCROLL_BARS
TREE_SITTER WEBP XIM GTK3 ZLIB

Important settings:
value of $LC_MONETARY: en_US.UTF-8
value of $LC_NUMERIC: en_US.UTF-8
value of $LC_TIME: en_US.UTF-8
value of $LANG: en_US.UTF-8
value of $XMODIFIERS: fcitx
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
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 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 rmc iso-transl tooltip cconv eldoc paren electric
uniquify ediff-hook vc-hooks lisp-float-type elisp-mode mwheel
term/pgtk-win pgtk-win term/common-win touch-screen pgtk-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 gtk pgtk
lcms2 multi-tty move-toolbar make-network-process native-compile emacs)

Memory information:
((conses 16 49610 11031) (symbols 48 5334 0) (strings 32 13417 2300)
(string-bytes 1 392723) (vectors 16 8817)
(vector-slots 8 124703 9243) (floats 8 22 12) (intervals 56 397 0)
(buffers 992 11))