bug#81610: 30.2; [PATCH] NS; NSRangeException when enabling tool-bar-mode

> Cc: [email protected]
> Date: Wed, 12 Aug 2026 16:54:06 +0300
> From: Yavor Doganov <[email protected]>
> 
> If I customize the tool-bar-mode variable to nil then the toolbar is
> not displayed, as expected.  However, if I enable it explicitly with
> the interactive command, an exception is thrown: a dialog "Critical
> Error in emacs" appears containing "NSRangeException: Index 0 is out
> of range 0 (in 'objectAtIndex:')".  Emacs then aborts.
> 
> Steps to reproduce:
> 
>   1. emacs -Q --eval "(tool-bar-mode -1)"
>   2. M-x tool-bar-mode RET
> 
> Backtrace and proposed patch below based on the master branch.
> 
> In GNU Emacs 30.2 (build 2, x86_64-pc-linux-gnu, NS
>  gnustep-gui-0.32.0) of 2026-07-04, modified by Debian built on
>  patilan
> Windowing system distributor 'GNU', version 10.3.32
> System Description: Debian GNU/Linux forky/sid
> 
> Configured using:
>  'configure --build x86_64-linux-gnu --prefix=/usr
>  --sharedstatedir=/var/lib --libexecdir=/usr/libexec
>  --localstatedir=/var/lib --infodir=/usr/share/info
>  --mandir=/usr/share/man --with-libsystemd --with-pop=yes
>  --enable-locallisppath=/etc/emacs:/usr/local/share/emacs/30.2/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/30.2/site-lisp:/usr/share/emacs/site-lisp
>  --with-sound=alsa --without-gconf --with-mailutils --build
>  x86_64-linux-gnu --prefix=/usr --sharedstatedir=/var/lib
>  --libexecdir=/usr/libexec --localstatedir=/var/lib
>  --infodir=/usr/share/info --mandir=/usr/share/man --with-libsystemd
>  --with-pop=yes
>  --enable-locallisppath=/etc/emacs:/usr/local/share/emacs/30.2/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/30.2/site-lisp:/usr/share/emacs/site-lisp
>  --with-sound=alsa --without-gconf --with-mailutils --with-ns
>  --disable-ns-self-contained --without-gif --without-jpeg
>  --without-png --without-rsvg --without-tiff --without-webp 'CFLAGS=-g
>  -O2 -Werror=implicit-function-declaration
>  -ffile-prefix-map=/build/reproducible-path/emacs-30.2+1=. -fstack-protector-strong
>  -fstack-clash-protection -Wformat -Werror=format-security
>  -fcf-protection -Wall' 'CPPFLAGS=-Wdate-time -D_FORTIFY_SOURCE=2'
>  LDFLAGS=-Wl,-z,relro'
> 
> Configured features:
> ACL DBUS GMP GNUTLS GPM LCMS2 LIBSELINUX LIBSYSTEMD LIBXML2 MODULES
> NATIVE_COMP NOTIFY INOTIFY NS PDUMPER SECCOMP SOUND SQLITE3 THREADS
> TOOLKIT_SCROLL_BARS TREE_SITTER XIM ZLIB
> 
> (gdb) break -[NSException raise]
> ❌️ Function "-[NSException raise]" not defined.
> Make breakpoint pending on future shared library load? (y or [n]) y
> Breakpoint 1 (-[NSException raise]) pending.
> (gdb) r -Q --eval "(tool-bar-mode -1)"
> Starting program: /home/yavor/src/emacs/src/emacs -Q --eval "(tool-bar-mode -1)"
> [Thread debugging using libthread_db enabled]
> Using host libthread_db library "/usr/lib/x86_64-linux-gnu/libthread_db.so.1".
> ⚠️ warning: Corrupted shared library list: 0x5555564e04b0 != 0x5555564df930
> [New Thread 0x7fffe8d5e6c0 (LWP 246730)]
> 
> Thread 1 "emacs" hit Breakpoint 1, -[NSException raise] (self=0x5555574f8030, 
>     _cmd=0x7ffff758d640 <_OBJC_SELECTOR_TABLE+128>)
>     at ./Source/NSException.m:1602
> ⚠️ warning: 1602	./Source/NSException.m: Няма такъв файл или директория
> (gdb) bt
> #0  -[NSException raise]
>     (self=0x5555574f8030, _cmd=0x7ffff758d640 <_OBJC_SELECTOR_TABLE+128>)
>     at ./Source/NSException.m:1602
> #1  0x00007ffff71c02b4 in -[GSArray objectAtIndex:]
>     (self=0x555557b78bc0, _cmd=<optimized out>, index=0)
>     at ./Source/GSArray.m:355
> #2  0x00007ffff7c1dddd in -[NSToolbar _removeItemAtIndex:broadcast:]
>     (self=0x555557a87500, _cmd=<optimized out>, index=0, broadcast=0 '\000')
>     at ./Source/NSToolbar.m:1270
> #3  0x00007ffff7c1dfed in -[NSToolbar _removeItemAtIndex:broadcast:]
>     (self=0x555557fb5980, _cmd=<optimized out>, index=0, broadcast=<optimized out>) at ./Source/NSToolbar.m:1284
> #4  0x0000555555851b79 in -[EmacsToolbar clearAll]
>     (self=0x555557fb5980, _cmd=<optimized out>) at nsmenu.m:1310
> #5  0x00005555558569de in update_frame_tool_bar_1
>     (f=0x5555560725a0, toolbar=0x555557fb5980) at nsmenu.m:1133
> #6  0x0000555555662e44 in redisplay_window
>     (window=0x5555560f1105, just_this_one_p=just_this_one_p@entry=false)
>     at xdisp.c:21545
> #7  0x0000555555663adb in redisplay_window_0 (window=<optimized out>)
>     at xdisp.c:18531
> #8  0x0000555555773a29 in internal_condition_case_1
>     (bfun=bfun@entry=0x555555663ab0 <redisplay_window_0>, arg=0x5555560f1105, handlers=<optimized out>, hfun=hfun@entry=0x5555556149b0 <redisplay_window_error>) at eval.c:1736
> #9  0x0000555555611c85 in redisplay_windows (window=0x5555560f1105)
>     at xdisp.c:18500
> #10 0x0000555555647cc0 in redisplay_internal () at xdisp.c:17917
> #11 0x0000555555649b75 in redisplay () at xdisp.c:17063
> #12 0x00005555556f0582 in read_char
>     (commandflag=<optimized out>, map=map@entry=0x7fffecf61563, prev_event=<optimized out>, used_mouse_menu=used_mouse_menu@entry=0x7fffffffd76b, end_time=end_time@entry=0x0) at keyboard.c:2711
> #13 0x00005555556f35e3 in read_key_sequence
>     (keybuf=keybuf@entry=0x7fffffffd8b0, prompt=prompt@entry=0x0, dont_downcase_last=dont_downcase_last@entry=false, can_return_switch_frame=can_return_switch_frame@entry=true, fix_current_buffer=fix_current_buffer@entry=true, prevent_redisplay=prevent_redisplay@entry=false, disable_text_conversion_p=false)
>     at keyboard.c:11224
> #14 0x00005555556f5754 in command_loop_1 () at keyboard.c:1424
> #15 0x00005555557739a4 in internal_condition_case
>     (bfun=bfun@entry=0x5555556f55a0 <command_loop_1>, handlers=handlers@entry=0x90, hfun=hfun@entry=0x5555556e7b30 <cmd_error>) at eval.c:1712
> #16 0x00005555556df366 in command_loop_2 (handlers=0x90) at keyboard.c:1163
> #17 0x00005555557738fe in internal_catch
>     (tag=tag@entry=0x12270, func=func@entry=0x5555556df340 <command_loop_2>, arg=arg@entry=0x90) at eval.c:1392
> #18 0x00005555556df303 in command_loop () at keyboard.c:1141
> #19 0x00005555556e76e1 in recursive_edit_1 () at keyboard.c:749
> #20 0x00005555556e7a68 in Frecursive_edit () at keyboard.c:832
> #21 0x00005555555f1de8 in main (argc=<optimized out>, argv=<optimized out>)
>     at emacs.c:2635
> (gdb) fr 3
> #3  0x00007ffff7c1dfed in -[NSToolbar _removeItemAtIndex:broadcast:] (
>     self=0x555557fb5980, _cmd=<optimized out>, index=0, 
>     broadcast=<optimized out>) at ./Source/NSToolbar.m:1284
> ⚠️ warning: 1284	./Source/NSToolbar.m: Няма такъв файл или директория
> (gdb) po self
> <EmacsToolbar: 0x555557fb5980>
> (gdb) po _items
> ("<<NSToolbarItem: 0x555557fb5210> - <5864062930753Open>>", "<<NSToolbarItem: 0x555557fb4ac0> - <5864062916976Open Directory>>", "<<NSToolbarItem: 0x555557fb42f0> - <5864062922955Close>>", "<<NSToolbarItem: 0x555557fb3b20> - <5864062924951Save>>", "<<NSToolbarItem: 0x555557fb3350> - <5864062937190Undo>>", "<<NSToolbarItem: 0x555557fb2b80> - <5864062939314Cut>>", "<<NSToolbarItem: 0x555557fb23b0> - <5864062940411Copy>>", "<<NSToolbarItem: 0x555557fb1bc0> - <5864063816493Paste>>", "<<NSToolbarItem: 0x555557fb13f0> - <5864064151308Search>>")
> (gdb) down
> #2  0x00007ffff7c1dddd in -[NSToolbar _removeItemAtIndex:broadcast:] (
>     self=0x555557a87500, _cmd=<optimized out>, index=0, broadcast=0 '\000')
>     at ./Source/NSToolbar.m:1270
> 1270	in ./Source/NSToolbar.m
> (gdb) po self
> <EmacsToolbar: 0x555557a87500>
> (gdb) po _items
> ()
> 
> Notice that in GDB frames 2 and 3 there are two distinct EmacsToolbar
> instances for a single Emacs frame.  The one from GDB frame 2,
> 0x555557a87500, is a "parasite" object: it is initialized at frame
> creation and toolbar items are never insterted in it.
> 
> GNUstep's NSToolbar implementation of -removeItemAtIndex: (called from
> EmacsToolbar -clearAll, nsmenu.m:1310) calls the private method
> -_removeItemAtIndex:broadcast: which calls itself recursively,
> dispatching the method call to all instances of the same class with
> identical identifiers (see the TRANSMIT macro definition in
> gnustep-gui/Source/NSToolbar.m:1205).  The goal here is to update the
> toolbars of the app's other windows ("frames" in Emacs terminology) if
> the identifiers match.
> 
> Because this first EmacsToolbar instance doesn't have any toolbar
> items, an exception occurs.

Alan, any comments to the patch?  Because it's definitely
macOS-specific.