bug#65837: 30.0.50; Debugger in non-main threads

[Helmut Eller <eller.helmut@gmail.com>]

When the debugger is entered in a non-main thread, like so

  emacs -Q --eval '(make-thread (lambda() (debug)))'

Then debugger-quit doesn't work as usual, instead it prints

  debugger-quit: No catch for tag: top-level, nil

or it prints

  Back to top level

but doesn't actually close the debugger window.

Also, debugger-continue doesn't work as usual, instead it sometimes prints:

  debugger-continue: No catch for tag: exit, nil

sometimes it prints:

  Continuing.

without deleting the debugger window, sometimes it manages to leave the
debugger.

If Emacs is started with "emacs -Q -nw" then the behaviour seems to be a
bit more uniform, but equally useless.

Helmut


In GNU Emacs 30.0.50 (build 192, x86_64-pc-linux-gnu, GTK+ Version
 3.24.37, cairo version 1.16.0) of 2023-09-09 built on caladan
Repository revision: e865ee05d7f974bace724dd241a311c753006933
Repository branch: interruptible-condition-wait
Windowing system distributor 'The X.Org Foundation', version 11.0.12101007
System Description: Debian GNU/Linux 12 (bookworm)

Configured using:
 'configure --enable-checking=yes --with-xpm=ifavailable
 --with-gif=ifavailable 'CFLAGS=-g -O1''

Configured features:
CAIRO DBUS FREETYPE GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG LIBSELINUX
LIBSYSTEMD LIBXML2 MODULES NOTIFY INOTIFY PDUMPER PNG SECCOMP SOUND
SQLITE3 THREADS TIFF TOOLKIT_SCROLL_BARS WEBP X11 XDBE XIM XINPUT2 GTK3
ZLIB