Dear Bug Team!
XEmacs 21.5-b6 crashed with an assert. I was using it to read mail under VM, and
garbage collection was going on. I've included the stack trace and the lisp
stack trace...
Lisp backtrace follows:
  # (unwind-protect ...)
  # (unwind-protect ...)
  # (unwind-protect ...)
  # (unwind-protect ...)
  # (unwind-protect ...)
  # (unwind-protect ...)
  # (unwind-protect ...)
  # (condition-case ... . error)
  # (catch top-level ...)
Core was generated by `xemacs-21.5-b6'.
Program terminated with signal 6, Abort trap.
Reading symbols from /usr/lib/libz.so.2...done.
Reading symbols from /usr/X11R6/lib/libXpm.so.4...done.
Reading symbols from /usr/X11R6/lib/libXmu.so.6...done.
Reading symbols from /usr/X11R6/lib/libXt.so.6...done.
Reading symbols from /usr/X11R6/lib/libXext.so.6...done.
Reading symbols from /usr/X11R6/lib/libX11.so.6...done.
Reading symbols from /usr/X11R6/lib/libSM.so.6...done.
Reading symbols from /usr/X11R6/lib/libICE.so.6...done.
Reading symbols from /usr/lib/libncurses.so.5...done.
Reading symbols from /usr/lib/libm.so.2...done.
Reading symbols from /usr/lib/libutil.so.3...done.
Reading symbols from /usr/lib/libxpg4.so.3...done.
Reading symbols from /usr/lib/libc.so.4...done.
Reading symbols from /usr/X11R6/lib/libXThrStub.so.6...done.
Reading symbols from /usr/X11R6/lib/X11/locale/common/xlcDef.so.2...done.
Reading symbols from /usr/libexec/ld-elf.so.1...done.
#0  0x284ab764 in kill () from /usr/lib/libc.so.4
(gdb) bt
#0  0x284ab764 in kill () from /usr/lib/libc.so.4
#1  0x80be631 in fatal_error_signal (sig=6) at emacs.c:3358
#2  0x9fbfffac in ?? ()
#3  0x80bf703 in really_abort () at emacs.c:4189
#4  0x80bf517 in assert_failed (file=0x821f73f "alloc.c", line=2410, 
    expr=0x821ff92 "!gc_in_progress") at emacs.c:3540
#5  0x8083a10 in free_managed_lcrecord (lcrecord_list=137148032, 
    lcrecord=142701632) at alloc.c:2410
#6  0x80d3cb3 in event_stream_disable_wakeup (id=13249, async_p=0)
    at event-stream.c:1351
#7  0x80da81f in Fdisable_timeout (id=26499) at event-stream.c:1468
#8  0x81317c6 in disable_glyph_animated_timeout (i=13249) at glyphs.c:4969
#9  0x81e91a8 in x_finalize_image_instance (p=0x92b2e00) at glyphs-x.c:437
#10 0x8131e0a in finalize_image_instance (header=0x92b2e00, for_disksave=0)
    at glyphs.c:1045
#11 0x8083f6f in sweep_lcrecords_1 (prev=0x829aed8, used=0x9fbff614)
    at alloc.c:2756
#12 0x8084dfe in gc_sweep () at alloc.c:3341
#13 0x808555f in garbage_collect_1 () at alloc.c:3736
#14 0x80c4d33 in Ffuncall (nargs=2, args=0x9fbff714) at eval.c:3436
#15 0x80c97ae in call1 (fn=139224676, arg0=145524316) at eval.c:4143
#16 0x80d6c6a in execute_internal_event (event=145524316)
    at event-stream.c:3099
#17 0x80d90d9 in Fdispatch_event (event=145524316) at event-stream.c:4409
#18 0x809f648 in Fcommand_loop_1 () at cmdloop.c:585
#19 0x809f8f6 in command_loop_1 (dummy=137172996) at cmdloop.c:497
#20 0x80c1a7f in condition_case_1 (handlers=137173092, 
    bfun=0x809f8b8 <command_loop_1>, barg=137172996, 
    hfun=0x809f968 <cmd_error>, harg=137172996) at eval.c:1692
---Type <return> to continue, or q <return> to quit---
#21 0x809fa5f in command_loop_2 (dummy=137172996) at cmdloop.c:259
#22 0x80ca14c in internal_catch (tag=137253348, 
    func=0x809fa1c <command_loop_2>, arg=137172996, threw=0x0) at eval.c:1323
#23 0x809eeb2 in initial_command_loop (load_me=137172996) at cmdloop.c:308
#24 0x80bd9cd in xemacs_21_5_b6_i386_unknown_freebsd4_3 (argc=1, 
    argv=0x9fbffafc, envp=0x9fbffb04, restart=0) at emacs.c:2312
#25 0x80bf849 in main (argc=1, argv=0x9fbffafc, envp=0x9fbffb04)
    at emacs.c:2749
#26 0x807fc15 in _start ()
================================================================
System Info to help track down your bug:
---------------------------------------
uname -a: FreeBSD 
vijayr.bangalore.yahoo.com 4.3 Fri Aug 31 22:03:39 IST 2001
./configure  '--prefix=/usr'
XEmacs 21.5-b6 "bok choi" configured for `i386-unknown-freebsd4.3'.
Compilation / Installation:
  Source code location:              /usr/tmp/vijayr/homes/vijayr/xemacs-21.5.6
  Installation prefix:               /usr
  Runtime library search path:       /usr/X11R6/lib:/usr/libexec
  Operating system description file: `s/freebsd.h'
  Machine description file:          `m/intel386.h'
  Compiler:                          gcc -g -O3 -Wall -Wno-switch -Winline
-Wmissing-prototypes -Wsign-compare -Wshadow -Wpointer-arith
  Relocating allocator for buffers:  yes
  GNU version of malloc:             yes
Window System:
  Compiling in support for the X window system:
    - X Windows headers location:                 /usr/X11R6/include
    - X Windows libraries location:               /usr/X11R6/lib
    - Handling WM_COMMAND properly.
  Using Lucid menubars.
  Using Lucid scrollbars.
TTY:
  Compiling in support for ncurses.
Images:
  Compiling in support for GIF  images (builtin).
  Compiling in support for XPM  images.
  WARNING: -----------------------------------------------------------
  WARNING: Compiling without PNG image support.
  WARNING: You should strongly consider installing the PNG libraries.
  WARNING: Otherwise certain images and glyphs may not display.
  WARNING: (a copy may be found in 
ftp://ftp.xemacs.org/pub/xemacs/aux)
  WARNING: -----------------------------------------------------------
Sound:
  Compiling in support for sound (native).
Databases:
  Compiling in support for Berkeley database.
  Compiling in support for DBM.
Internationalization:
Mail:
  Compiling in support for "flock" mail spool file locking method.
Other Features:
  Inhibiting IPv6 canonicalization at startup.
  Compiling in support for dynamic shared object modules.
  Compiling in support for extra debugging code.
  WARNING: ---------------------------------------------------------
  WARNING: Compiling in support for runtime error checking.
  WARNING: XEmacs will run noticeably more slowly as a result.
  WARNING: Error checking is on by default for XEmacs beta releases.
  WARNING: ---------------------------------------------------------
Load-Path Lisp Shadows:
----------------------
(/home_extra/vijayr/elisp/vcard /usr/lib/xemacs/xemacs-packages/lisp/gnus/vcard
/home_extra/vijayr/elisp/p4 /usr/lib/xemacs/xemacs-packages/lisp/prog-modes/p4
/home_extra/vijayr/elisp/folding
/usr/lib/xemacs/xemacs-packages/lisp/text-modes/folding)
Installed XEmacs Packages:
-------------------------
((zenirc:version 1.13 :type regular)
 (xslt-process :version 1.06 :type regular)
 (xslide :version 1.01 :type regular)
 (xemacs-devel :version 1.43 :type single-file)
 (xemacs-base :version 1.61 :type regular)
 (w3 :version 1.22 :type regular)
 (vm :version 7.03 :type regular)
 (viper :version 1.33 :type regular)
 (view-process :version 1.11 :type regular)
 (vhdl :version 1.15 :type regular)
 (vc-cc :version 1.18 :type regular)
 (vc :version 1.3 :type regular)
 (tpu :version 1.12 :type regular)
 (tooltalk :version 1.13 :type regular)
 (tm :version 1.32 :type regular)
 (time :version 1.11 :type regular)
 (textools :version 1.12 :type regular)
 (text-modes :version 1.4 :type single-file)
 (texinfo :version 1.2 :type regular)
 (supercite :version 1.19 :type regular)
 (strokes :version 1.08 :type regular)
 (speedbar :version 1.23 :type regular)
 (sounds-wav :version 1.1 :type regular)
 (sounds-au :version 1.1 :type regular)
 (slider :version 1.13 :type regular)
 (sieve :version 1.02 :type regular)
 (sh-script :version 1.14 :type regular)
 (sgml :version 1.08 :type regular)
 (semantic :version 1.12 :type regular)
 (scheme :version 1.11 :type regular)
 (rmail :version 1.13 :type regular)
 (reftex :version 1.25 :type regular)
 (psgml :version 1.27 :type regular)
 (ps-print :version 1.03 :type regular)
 (prog-modes
  :version
   1
   .53
    :type
     single-file)
 (pcomplete :version 1.01 :type regular)
 (pcl-cvs :version 1.6 :type regular)
 (pc :version 1.21 :type single-file)
 (os-utils :version 1.26 :type single-file)
 (net-utils :version 1.24 :type single-file)
 (mmm-mode :version 1.0 :type regular)
 (misc-games :version 1.15 :type single-file)
 (mine :version 1.14 :type regular)
 (mh-e :version 1.14 :type regular)
 (mew :version 1.17 :type regular)
 (mailcrypt :version 2.11 :type regular)
 (mail-lib :version 1.44 :type regular)
 (liece :version 1.02 :type regular)
 (jde :version 1.34 :type regular)
 (ispell :version 1.24 :type regular)
 (ilisp :version 1.2 :type regular)
 (igrep :version 1.08 :type regular)
 (idlwave :version 1.25 :type regular)
 (ibuffer :version 1.04 :type regular)
 (hm--html-menus :version 1.18 :type regular)
 (gnus :version 1.59 :type regular)
 (gnats :version 1.14 :type regular)
 (games :version 1.13 :type regular)
 (fsf-compat :version 1.11 :type single-file)
 (frame-icon :version 1.09 :type regular)
 (forms :version 1.14 :type regular)
 (footnote :version 1.14 :type regular)
 (eudc :version 1.36 :type regular)
 (eterm :version 1.13 :type regular)
 (eshell :version 1.03 :type regular)
 (emerge :version 1.09 :type regular)
 (elib :version 1.1 :type single-file)
 (eieio :version 1.02 :type regular)
 (efs :version 1.28 :type regular)
 (edt :version 1.12 :type regular)
 (edit-utils :version 1.82 :type single-file)
 (ediff :version 1.39 :type regular)
 (edebug :version 1.14 :type regular)
 (dired :version 1.11 :type regular)
 (debug :version 1.14 :type regular)
 (crisp :version 1.12 :type regular)
 (cookie :version 1.14 :type regular)
 (clearcase :version 1.03 :type regular)
 (cc-mode :version 1.27 :type regular)
 (calendar :version 1.18 :type regular)
 (calc :version 1.19 :type regular)
 (c-support :version 1.16 :type single-file)
 (build :version 1.05 :type regular)
 (bbdb :version 1.2 :type regular)
 (auctex :version 1.3 :type regular)
 (apel :version 1.21 :type regular)
 (ada :version 1.1 :type regular))
Features:
--------
(xemacsbug shadow outline view-less view compile vm-crypto vm-minibuf vm-pop
bbdb-gui bbdb-hooks vm-page vm-mime vm-save vm-toolbar vm-summary tapestry
vm-motion vm-message vm-menu vm-folder vm-misc vm-mouse vm-window bbdb-vm
bbdb-snarf mail-extr bbdb-com mail-abbrevs bbdb timezone vm-autoload vm-vars
vm-version vm vm-startup lazy-lock highlight-headers cpp-font-lock regexp-opt
font-lock time mycc-mode expand skeleton cc-mode cc-align cc-cmds cc-engine
cc-styles cc-langs cc-vars wid-edit cc-menus imenu cc-defs func-menu crypt
crypt++ efs-cu efs-x19.15 efs-fnh efs-ovwrt efs-auto cus-face dired-faces
dired-xemacs dired smtpmail time-stamp sendmail rfc822 zenirc-autoloads
xslt-process-autoloads xslide-autoloads xemacs-devel-autoloads
xemacs-base-autoloads w3-autoloads vm-autoloads viper-autoloads
view-process-autoloads vhdl-autoloads vc-cc-autoloads vc-autoloads tpu-autoloads
tooltalk-autoloads tm-autoloads time-autoloads textools-autoloads
text-modes-autoloads texinfo-autoloads supercite-autoloads strokes-autoloads
speedbar-autoloads sounds-wav-autoloads sounds-au-autoloads slider-autoloads
sieve-autoloads sh-script-autoloads sgml-autoloads semantic-autoloads
scheme-autoloads rmail-autoloads reftex-autoloads psgml-autoloads
ps-print-autoloads prog-modes-autoloads pcomplete-autoloads pcl-cvs-autoloads
pc-autoloads os-utils-autoloads net-utils-autoloads mmm-mode-autoloads
misc-games-autoloads mine-autoloads mh-e-autoloads mew-autoloads
mailcrypt-autoloads mail-lib-autoloads liece-autoloads jde-autoloads
ispell-autoloads ilisp-autoloads igrep-autoloads idlwave-autoloads
ibuffer-autoloads hm--html-menus-autoloads gnus-autoloads gnats-autoloads
games-autoloads fsf-compat-autoloads frame-icon-autoloads forms-autoloads
footnote-autoloads eudc-autoloads eterm-autoloads eshell-autoloads
emerge-autoloads elib-autoloads eieio-autoloads efs-autoloads edt-autoloads
edit-utils-autoloads ediff-autoloads edebug-autoloads dired-autoloads
debug-autoloads crisp-autoloads cookie-autoloads clearcase-autoloads
cc-mode-autoloads calendar-autoloads calc-autoloads c-support-autoloads
build-autoloads bbdb-autoloads auctex-autoloads apel-autoloads ada-autoloads
src-autoloads loadhist rsz-minibuf auto-show fontl-hooks x-iso8859-1 code-cmds
gutter-items menubar-items x-menubar mode-motion mouse behavior itimer auto-save
lisp-mode easymenu iso8859-1 page buff-menu lib-complete cus-file derived frame
env text-props obsolete cus-start custom widget cl-extra mini-cl cl cl-19
packages backquote very-early-lisp unicode lucid-scrollbars cut-buffer
lucid-menubars x c-balloon-help tty-frames tty toolbar native-sound scrollbar
unix-processes multicast network-streams subprocesses modules
menu-accelerator-support menubar berkeley-db dbm md5 xemacs gutter gif xpm xbm
lisp-float-type file-coding berkeley-unix devices window-system base64)