bug#61162: 30.0.50; RET in source files that are being displayed by gud no longer works

bug#61162: 30.0.50; RET in source files that are being displayed by gud no longer works

[Michael Welsh Duggan]

Create a trivial C program.  Here's a good example:

    int main()
    {
      return 0;
    }

Save it as foo.c, and compile it with debugging:

    gcc -ggdb3 -o foo foo.c

From emacs -Q, start gdb on foo:

    M-x gud-gdb RET 

In my case, since foo is the only executable in the dir, the command
line for gdb is already set up correctly as:

    gdb --fullname foo

Hit RET.  You should be at the gdb prompt.  Start the program:

    start RET

You should now get another window with foo.c in it for context.  Switch
to that buffer and type RET.

    C-x o
    RET

In my case, I get:

    comint-send-input: Current buffer has no process

This is new and broken behavior.  The expected behavior is that a
newline is inserted in the buffer.


In GNU Emacs 30.0.50 (build 2, x86_64-pc-linux-gnu, X toolkit, cairo
 version 1.16.0) of 2023-01-25 built on miko
Repository revision: 8b87d095acfb23b527f955873a59dd9c13ffc9b4
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12101004
System Description: Debian GNU/Linux bookworm/sid

Configured using:
 'configure --without-toolkit-scroll-bars --with-x-toolkit=lucid
 --with-native-compilation --with-xinput2 'CFLAGS=-Og -ggdb'
 --with-tree-sitter'

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GPM GSETTINGS HARFBUZZ JPEG
JSON LCMS2 LIBOTF LIBSELINUX LIBSYSTEMD LIBXML2 M17N_FLT MODULES
NATIVE_COMP NOTIFY INOTIFY PDUMPER PNG RSVG SECCOMP SOUND SQLITE3
THREADS TIFF TREE_SITTER WEBP X11 XAW3D XDBE XIM XINPUT2 XPM LUCID ZLIB

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

Major mode: Group

Minor modes in effect:
  gnus-topic-mode: t
  cursor-sensor-mode: t
  gnus-undo-mode: t
  display-time-mode: t
  magit-wip-initial-backup-mode: t
  magit-wip-before-change-mode: t
  magit-wip-after-apply-mode: t
  magit-wip-after-save-mode: t
  magit-wip-mode: t
  global-git-commit-mode: t
  magit-auto-revert-mode: t
  shell-dirtrack-mode: t
  server-mode: t
  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
  font-lock-mode: t
  buffer-read-only: t
  line-number-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t

Load-path shadows:
/home/md5i/.config/emacs/elpa/transient-0.3.7/transient hides /home/md5i/src/emacs/md5i/lisp/transient

Features:
(shadow emacsbug emacs-news-mode noutline outline pulse
display-line-numbers magit-bookmark bookmark man sieve-mode pcmpl-unix
find-dired jka-compr shortdoc help-fns radix-tree gud goto-addr
mailalias smtpmail canlock generic etags fileloop generator xref
calc-misc calc-alg calc-ext calc-menu calc calc-loaddefs rect calc-macs
vc-hg vc-bzr vc-src vc-sccs vc-svn vc-cvs vc-rcs log-view bug-reference
sh-script smie executable dabbrev grep misearch multi-isearch copyright
time-stamp whitespace tabify vc cmake-mode thingatpt rst magit-extras
dired-aux face-remap vc-git vc-dispatcher flow-fill shr-color color
mm-archive qp mule-util sort gnus-cite mail-extr textsec uni-scripts
idna-mapping ucs-normalize uni-confusable textsec-check gnus-async
gnus-bcklg gnus-ml disp-table gnus-topic cursor-sensor nndraft nnmh
nnfolder utf-7 epa-file network-stream gnus-agent gnus-srvr gnus-score
score-mode nnvirtual gnus-msg gnus-art mm-uu mml2015 mm-view mml-smime
smime dig gnus-cache gnus-sum shr pixel-fill kinsoku url-file svg
gnus-demon nntp gnus-group gnus-undo gnutls gnus-start gnus-dbus
gnus-cloud gnus-spec gnus-win flyspell ispell view pacproxy descr-text
tramp tramp-loaddefs trampver tramp-integration cus-edit pp cus-load
files-x tramp-compat parse-time iso8601 ls-lisp time sieve-manage sasl
sasl-anonymous sasl-login sasl-plain rng-loc rng-uri rng-parse rng-match
rng-dt rng-util rng-pttrn nxml-parse nxml-ns nxml-enc xmltok nxml-util
sgml-mode facemenu dom python project compat pcase treesit ps-print
ps-print-loaddefs lpr picture nm dbus xml magit-submodule magit-obsolete
magit-blame magit-stash magit-reflog magit-bisect magit-push magit-pull
magit-fetch magit-clone magit-remote magit-commit magit-sequence
magit-notes magit-worktree magit-tag magit-merge magit-branch
magit-reset magit-files magit-refs magit-status magit magit-repos
magit-apply magit-wip magit-log which-func imenu magit-diff smerge-mode
diff diff-mode easy-mmode git-commit log-edit pcvs-util add-log
magit-core magit-autorevert autorevert filenotify magit-margin
magit-transient magit-process with-editor shell pcomplete server
magit-mode transient comp comp-cstr warnings icons rx cl-extra edmacro
kmacro help-mode format-spec magit-git magit-section magit-utils crm
dash nnimap nnmail gnus-int mail-source gnus-range message sendmail
yank-media rfc822 mml mml-sec epa mm-decode mm-bodies mm-encode
mailabbrev gmm-utils mailheader utf7 nnoo gnus wid-edit nnheader
gnus-util time-date mail-utils range gnus-o365-oauth2 oauth2 url-http
url-auth mail-parse rfc2231 rfc2047 rfc2045 mm-util ietf-drums
mail-prsvr url-gw nsm puny plstore generated generic-x epg rfc6068
epg-config ediff ediff-merg ediff-mult ediff-wind ediff-diff ediff-help
ediff-init ediff-util dired-x dired dired-loaddefs compile
text-property-search comint ansi-osc ring ansi-color cc-mode cc-fonts
cc-guess cc-menus cc-cmds cc-styles cc-align cc-engine cc-vars cc-defs
derived magit-autoloads git-commit-autoloads magit-section-autoloads
transient-autoloads with-editor-autoloads debbugs-autoloads
ahg-autoloads flycheck-autoloads pkg-info-autoloads epl-autoloads
js2-mode-autoloads company-autoloads rainbow-delimiters-autoloads info
debian-el package browse-url url url-proxy url-privacy url-expand
url-methods url-history url-cookie generate-lisp-file url-domsuf
url-util mailcap url-handlers url-parse auth-source cl-seq eieio
eieio-core cl-macs password-cache json subr-x map byte-opt gv bytecomp
byte-compile url-vars cl-loaddefs cl-lib 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 lcms2
dynamic-setting system-font-setting font-render-setting cairo x-toolkit
xinput2 x multi-tty make-network-process native-compile emacs)

Memory information:
((conses 16 2569013 179021)
 (symbols 48 54509 8)
 (strings 32 301965 34664)
 (string-bytes 1 9142322)
 (vectors 16 154479)
 (vector-slots 8 2479637 295788)
 (floats 8 1620 935)
 (intervals 56 113568 607)
 (buffers 984 156))

-- 
Michael Welsh Duggan
(md5i@md5i.com)

bug#61162: 30.0.50; RET in source files that are being displayed by gud no longer works

[Michael Welsh Duggan]

Michael Welsh Duggan <mwd@md5i.com> writes:

> Create a trivial C program.  Here's a good example:
>
>     int main()
>     {
>       return 0;
>     }
>
> Save it as foo.c, and compile it with debugging:
>
>     gcc -ggdb3 -o foo foo.c
>
> From emacs -Q, start gdb on foo:
>
>     M-x gud-gdb RET 
>
> In my case, since foo is the only executable in the dir, the command
> line for gdb is already set up correctly as:
>
>     gdb --fullname foo
>
> Hit RET.  You should be at the gdb prompt.  Start the program:
>
>     start RET
>
> You should now get another window with foo.c in it for context.  Switch
> to that buffer and type RET.
>
>     C-x o
>     RET
>
> In my case, I get:
>
>     comint-send-input: Current buffer has no process
>
> This is new and broken behavior.  The expected behavior is that a
> newline is inserted in the buffer.

This appears to be caused by commit
a7b0b20c1bc758fa99fda96d06a266868aec3eea, which was supposed to fix
Bug#59605.

> In GNU Emacs 30.0.50 (build 2, x86_64-pc-linux-gnu, X toolkit, cairo
>  version 1.16.0) of 2023-01-25 built on miko
> Repository revision: 8b87d095acfb23b527f955873a59dd9c13ffc9b4
> Repository branch: master
> Windowing system distributor 'The X.Org Foundation', version 11.0.12101004
> System Description: Debian GNU/Linux bookworm/sid
>
> Configured using:
>  'configure --without-toolkit-scroll-bars --with-x-toolkit=lucid
>  --with-native-compilation --with-xinput2 'CFLAGS=-Og -ggdb'
>  --with-tree-sitter'
>
> Configured features:
> ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GPM GSETTINGS HARFBUZZ JPEG
> JSON LCMS2 LIBOTF LIBSELINUX LIBSYSTEMD LIBXML2 M17N_FLT MODULES
> NATIVE_COMP NOTIFY INOTIFY PDUMPER PNG RSVG SECCOMP SOUND SQLITE3
> THREADS TIFF TREE_SITTER WEBP X11 XAW3D XDBE XIM XINPUT2 XPM LUCID ZLIB
>
> Important settings:
>   value of $LANG: en_US.UTF-8
>   value of $XMODIFIERS: @im=ibus
>   locale-coding-system: utf-8-unix
>
> Major mode: Group
>
> Minor modes in effect:
>   gnus-topic-mode: t
>   cursor-sensor-mode: t
>   gnus-undo-mode: t
>   display-time-mode: t
>   magit-wip-initial-backup-mode: t
>   magit-wip-before-change-mode: t
>   magit-wip-after-apply-mode: t
>   magit-wip-after-save-mode: t
>   magit-wip-mode: t
>   global-git-commit-mode: t
>   magit-auto-revert-mode: t
>   shell-dirtrack-mode: t
>   server-mode: t
>   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
>   font-lock-mode: t
>   buffer-read-only: t
>   line-number-mode: t
>   auto-composition-mode: t
>   auto-encryption-mode: t
>   auto-compression-mode: t
>
> Load-path shadows:
> /home/md5i/.config/emacs/elpa/transient-0.3.7/transient hides /home/md5i/src/emacs/md5i/lisp/transient
>
> Features:
> (shadow emacsbug emacs-news-mode noutline outline pulse
> display-line-numbers magit-bookmark bookmark man sieve-mode pcmpl-unix
> find-dired jka-compr shortdoc help-fns radix-tree gud goto-addr
> mailalias smtpmail canlock generic etags fileloop generator xref
> calc-misc calc-alg calc-ext calc-menu calc calc-loaddefs rect calc-macs
> vc-hg vc-bzr vc-src vc-sccs vc-svn vc-cvs vc-rcs log-view bug-reference
> sh-script smie executable dabbrev grep misearch multi-isearch copyright
> time-stamp whitespace tabify vc cmake-mode thingatpt rst magit-extras
> dired-aux face-remap vc-git vc-dispatcher flow-fill shr-color color
> mm-archive qp mule-util sort gnus-cite mail-extr textsec uni-scripts
> idna-mapping ucs-normalize uni-confusable textsec-check gnus-async
> gnus-bcklg gnus-ml disp-table gnus-topic cursor-sensor nndraft nnmh
> nnfolder utf-7 epa-file network-stream gnus-agent gnus-srvr gnus-score
> score-mode nnvirtual gnus-msg gnus-art mm-uu mml2015 mm-view mml-smime
> smime dig gnus-cache gnus-sum shr pixel-fill kinsoku url-file svg
> gnus-demon nntp gnus-group gnus-undo gnutls gnus-start gnus-dbus
> gnus-cloud gnus-spec gnus-win flyspell ispell view pacproxy descr-text
> tramp tramp-loaddefs trampver tramp-integration cus-edit pp cus-load
> files-x tramp-compat parse-time iso8601 ls-lisp time sieve-manage sasl
> sasl-anonymous sasl-login sasl-plain rng-loc rng-uri rng-parse rng-match
> rng-dt rng-util rng-pttrn nxml-parse nxml-ns nxml-enc xmltok nxml-util
> sgml-mode facemenu dom python project compat pcase treesit ps-print
> ps-print-loaddefs lpr picture nm dbus xml magit-submodule magit-obsolete
> magit-blame magit-stash magit-reflog magit-bisect magit-push magit-pull
> magit-fetch magit-clone magit-remote magit-commit magit-sequence
> magit-notes magit-worktree magit-tag magit-merge magit-branch
> magit-reset magit-files magit-refs magit-status magit magit-repos
> magit-apply magit-wip magit-log which-func imenu magit-diff smerge-mode
> diff diff-mode easy-mmode git-commit log-edit pcvs-util add-log
> magit-core magit-autorevert autorevert filenotify magit-margin
> magit-transient magit-process with-editor shell pcomplete server
> magit-mode transient comp comp-cstr warnings icons rx cl-extra edmacro
> kmacro help-mode format-spec magit-git magit-section magit-utils crm
> dash nnimap nnmail gnus-int mail-source gnus-range message sendmail
> yank-media rfc822 mml mml-sec epa mm-decode mm-bodies mm-encode
> mailabbrev gmm-utils mailheader utf7 nnoo gnus wid-edit nnheader
> gnus-util time-date mail-utils range gnus-o365-oauth2 oauth2 url-http
> url-auth mail-parse rfc2231 rfc2047 rfc2045 mm-util ietf-drums
> mail-prsvr url-gw nsm puny plstore generated generic-x epg rfc6068
> epg-config ediff ediff-merg ediff-mult ediff-wind ediff-diff ediff-help
> ediff-init ediff-util dired-x dired dired-loaddefs compile
> text-property-search comint ansi-osc ring ansi-color cc-mode cc-fonts
> cc-guess cc-menus cc-cmds cc-styles cc-align cc-engine cc-vars cc-defs
> derived magit-autoloads git-commit-autoloads magit-section-autoloads
> transient-autoloads with-editor-autoloads debbugs-autoloads
> ahg-autoloads flycheck-autoloads pkg-info-autoloads epl-autoloads
> js2-mode-autoloads company-autoloads rainbow-delimiters-autoloads info
> debian-el package browse-url url url-proxy url-privacy url-expand
> url-methods url-history url-cookie generate-lisp-file url-domsuf
> url-util mailcap url-handlers url-parse auth-source cl-seq eieio
> eieio-core cl-macs password-cache json subr-x map byte-opt gv bytecomp
> byte-compile url-vars cl-loaddefs cl-lib 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 lcms2
> dynamic-setting system-font-setting font-render-setting cairo x-toolkit
> xinput2 x multi-tty make-network-process native-compile emacs)
>
> Memory information:
> ((conses 16 2569013 179021)
>  (symbols 48 54509 8)
>  (strings 32 301965 34664)
>  (string-bytes 1 9142322)
>  (vectors 16 154479)
>  (vector-slots 8 2479637 295788)
>  (floats 8 1620 935)
>  (intervals 56 113568 607)
>  (buffers 984 156))

-- 
Michael Welsh Duggan
(md5i@md5i.com)

bug#61162: 30.0.50; RET in source files that are being displayed by gud no longer works

[Eli Zaretskii]

> From: Michael Welsh Duggan <mwd@md5i.com>
> Date: Tue, 31 Jan 2023 14:17:20 -0500
> 
> Michael Welsh Duggan <mwd@md5i.com> writes:
> 
> > Create a trivial C program.  Here's a good example:
> >
> >     int main()
> >     {
> >       return 0;
> >     }
> >
> > Save it as foo.c, and compile it with debugging:
> >
> >     gcc -ggdb3 -o foo foo.c
> >
> > From emacs -Q, start gdb on foo:
> >
> >     M-x gud-gdb RET 
> >
> > In my case, since foo is the only executable in the dir, the command
> > line for gdb is already set up correctly as:
> >
> >     gdb --fullname foo
> >
> > Hit RET.  You should be at the gdb prompt.  Start the program:
> >
> >     start RET
> >
> > You should now get another window with foo.c in it for context.  Switch
> > to that buffer and type RET.
> >
> >     C-x o
> >     RET
> >
> > In my case, I get:
> >
> >     comint-send-input: Current buffer has no process
> >
> > This is new and broken behavior.  The expected behavior is that a
> > newline is inserted in the buffer.
> 
> This appears to be caused by commit
> a7b0b20c1bc758fa99fda96d06a266868aec3eea, which was supposed to fix
> Bug#59605.

This current problem is part of fallout from commit 8bb5c1bfec.  That
commit was reverted on the emacs-29 branch, as it caused too much
trouble.  It was not reverted on master, as I still hope someone
motivated enough will step up to fix this without reverting back to
using easy-mmode, which we hoped to obsolete.

If you can find a fix on master, patches would be very welcome.
Failing that, I might eventually decide to revert that commit on
master as well.  There's a limit to the efforts I'm prepared to sink
into maintaining what is basically an obsolete package which uses a
GDB feature that GDB developers consider obsolete and may remove any
day (why don't you use "M-x gdb" instead?).

bug#61162: 30.0.50; RET in source files that are being displayed by gud no longer works

[Michael Welsh Duggan]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Michael Welsh Duggan <mwd@md5i.com>
>> Date: Tue, 31 Jan 2023 14:17:20 -0500
>> 
>> Michael Welsh Duggan <mwd@md5i.com> writes:
>> 
>> > Create a trivial C program.  Here's a good example:
>> >
>> >     int main()
>> >     {
>> >       return 0;
>> >     }
>> >
>> > Save it as foo.c, and compile it with debugging:
>> >
>> >     gcc -ggdb3 -o foo foo.c
>> >
>> > From emacs -Q, start gdb on foo:
>> >
>> >     M-x gud-gdb RET 
>> >
>> > In my case, since foo is the only executable in the dir, the command
>> > line for gdb is already set up correctly as:
>> >
>> >     gdb --fullname foo
>> >
>> > Hit RET.  You should be at the gdb prompt.  Start the program:
>> >
>> >     start RET
>> >
>> > You should now get another window with foo.c in it for context.  Switch
>> > to that buffer and type RET.
>> >
>> >     C-x o
>> >     RET
>> >
>> > In my case, I get:
>> >
>> >     comint-send-input: Current buffer has no process
>> >
>> > This is new and broken behavior.  The expected behavior is that a
>> > newline is inserted in the buffer.
>> 
>> This appears to be caused by commit
>> a7b0b20c1bc758fa99fda96d06a266868aec3eea, which was supposed to fix
>> Bug#59605.
>
> This current problem is part of fallout from commit 8bb5c1bfec.  That
> commit was reverted on the emacs-29 branch, as it caused too much
> trouble.  It was not reverted on master, as I still hope someone
> motivated enough will step up to fix this without reverting back to
> using easy-mmode, which we hoped to obsolete.

I'll try to look into that, but it might be beyond me.

> If you can find a fix on master, patches would be very welcome.
> Failing that, I might eventually decide to revert that commit on
> master as well.  There's a limit to the efforts I'm prepared to sink
> into maintaining what is basically an obsolete package which uses a
> GDB feature that GDB developers consider obsolete and may remove any
> day (why don't you use "M-x gdb" instead?).

I always use "M-x gud-gdb" because, historically, "M-x gdb" didn't
support multiple simultaneous gdb sessions.  If this is no longer the
case, I will see if I can change my habits.

-- 
Michael Welsh Duggan
(md5i@md5i.com)

bug#61162: 30.0.50; RET in source files that are being displayed by gud no longer works

[Eli Zaretskii]

> From: Michael Welsh Duggan <mwd@md5i.com>
> Cc: Michael Welsh Duggan <mwd@md5i.com>,  61162@debbugs.gnu.org
> Date: Tue, 31 Jan 2023 15:18:15 -0500
> 
> > If you can find a fix on master, patches would be very welcome.
> > Failing that, I might eventually decide to revert that commit on
> > master as well.  There's a limit to the efforts I'm prepared to sink
> > into maintaining what is basically an obsolete package which uses a
> > GDB feature that GDB developers consider obsolete and may remove any
> > day (why don't you use "M-x gdb" instead?).
> 
> I always use "M-x gud-gdb" because, historically, "M-x gdb" didn't
> support multiple simultaneous gdb sessions.  If this is no longer the
> case, I will see if I can change my habits.

This is no longer the case, if it ever was.  What exactly didn't work
for you when you tried several simultaneous sessions?  The buffer
where you type GDB commands is named "*gud-PROGRAM*", so you have
separate buffers for different sessions.  And if you start each one
from a separate Emacs frame, you should be able to have separate
multi-window configurations (see gdb-many-windows) for each session.

bug#61162: 30.0.50; RET in source files that are being displayed by gud no longer works

[Michael Welsh Duggan]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Michael Welsh Duggan <mwd@md5i.com>
>> Cc: Michael Welsh Duggan <mwd@md5i.com>,  61162@debbugs.gnu.org
>> Date: Tue, 31 Jan 2023 15:18:15 -0500
>> 
>> > If you can find a fix on master, patches would be very welcome.
>> > Failing that, I might eventually decide to revert that commit on
>> > master as well.  There's a limit to the efforts I'm prepared to sink
>> > into maintaining what is basically an obsolete package which uses a
>> > GDB feature that GDB developers consider obsolete and may remove any
>> > day (why don't you use "M-x gdb" instead?).
>> 
>> I always use "M-x gud-gdb" because, historically, "M-x gdb" didn't
>> support multiple simultaneous gdb sessions.  If this is no longer the
>> case, I will see if I can change my habits.
>
> This is no longer the case, if it ever was.  What exactly didn't work
> for you when you tried several simultaneous sessions?  The buffer
> where you type GDB commands is named "*gud-PROGRAM*", so you have
> separate buffers for different sessions.  And if you start each one
> from a separate Emacs frame, you should be able to have separate
> multi-window configurations (see gdb-many-windows) for each session.

Ah, I remember now.  It was the ability to debug the same program twice
at once that was lacking.  I haven't needed that ability recently.  (I
needed it in the past when dealing with a program that connected to
other instances of itself.)

-- 
Michael Welsh Duggan
(md5i@md5i.com)

bug#61162: 30.0.50; RET in source files that are being displayed by gud no longer works

[Eli Zaretskii]

> From: Michael Welsh Duggan <mwd@md5i.com>
> Cc: Michael Welsh Duggan <mwd@md5i.com>,  61162@debbugs.gnu.org
> Date: Wed, 01 Feb 2023 09:30:35 -0500
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > This is no longer the case, if it ever was.  What exactly didn't work
> > for you when you tried several simultaneous sessions?  The buffer
> > where you type GDB commands is named "*gud-PROGRAM*", so you have
> > separate buffers for different sessions.  And if you start each one
> > from a separate Emacs frame, you should be able to have separate
> > multi-window configurations (see gdb-many-windows) for each session.
> 
> Ah, I remember now.  It was the ability to debug the same program twice
> at once that was lacking.  I haven't needed that ability recently.  (I
> needed it in the past when dealing with a program that connected to
> other instances of itself.)

Are you sure you cannot have this if you manually rename one of the
GUD buffers?