bug#70049: 30.0.50; (server-running-p) in mode line freezes emacs

[Pedro A. Aranda]

Place the following file as init.el in a directory (e.g. ~/.demacs.d)


---- cut here ----
;; Mode line settings

(defun server-running-indicator()
  (when (server-running-p) "S "))
;;  (unless (null server-process) "S "))

;; (setq-default mode-line-right-align-edge 'right-fringe)
(setq-default mode-line-format
              (list
                     '(:eval (propertize (server-running-indicator)
                                         'face 'mode-line-buffer-id))

                     mode-line-modified
                     " "
                     mode-line-buffer-identification
                     " "
                     mode-line-position))
---- cut here ----

run emacs as
/usr/bin/emacs --init-directory ~/.demacs.d

On the emacs window, click on the lower left corner and resize it with
the mouse. No hangs are observed.

Now, active server-mode with
M-x server-mode

Try again to resize the emacs window with the mouse. Emacs freezes.

This doesn't happen if you use the commented line
(unless (null server-process) "S "))
instead of the
(when (server-running-p) "S "))


In GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version
 3.24.33, cairo version 1.16.0) of 2024-03-28 built on ee9499c728de
Repository revision: f1fe13ea057237f5426c93876488cb95be86156c
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12201001
System Description: Ubuntu 22.04.4 LTS

Configured using:
 'configure --prefix=/usr --program-suffix=30 --with-x
 --with-x-toolkit=gtk3 --with-cairo --with-compress-install
 --with-modules=yes --with-threads --with-included-regex --with-zlib
 --with-json --with-rsvg --with-small-ja-dic
 --with-native-compilation=aot --with-tree-sitter=no 'CFLAGS=-g -O2
 -ffile-prefix-map=/home/paag/emacs=. -flto=auto -ffat-lto-objects
 -flto=auto -ffat-lto-objects -fstack-protector-strong -Wformat
 -Werror=format-security' 'CPPFLAGS=-Wdate-time -D_FORTIFY_SOURCE=2'
 'LDFLAGS=-Wl,-Bsymbolic-functions -flto=auto -ffat-lto-objects
 -flto=auto -Wl,-z,relro''

Configured features:
CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG JSON
LIBSELINUX LIBXML2 MODULES NATIVE_COMP NOTIFY INOTIFY PDUMPER PNG RSVG
SECCOMP SOUND THREADS TIFF TOOLKIT_SCROLL_BARS X11 XDBE XIM XINPUT2 XPM
GTK3 ZLIB

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

Major mode: Fundamental

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
  blink-cursor-mode: t
  minibuffer-regexp-mode: t
  buffer-read-only: 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:
/usr/share/emacs/site-lisp/latex-cjk-thai/thai-word hides 
/usr/share/emacs/30.0.50/lisp/language/thai-word

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/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
dynamic-setting system-font-setting font-render-setting cairo gtk
x-toolkit xinput2 x multi-tty move-toolbar make-network-process
native-compile emacs)

Memory information:
((conses 16 51330 11727) (symbols 48 5230 0) (strings 32 13871 2528)
 (string-bytes 1 460407) (vectors 16 9073)
 (vector-slots 8 126676 10197) (floats 8 40 13) (intervals 56 375 16)
 (buffers 984 11))