Re: Fix to long-standing crashes in GC

[Lars Hansen]

For a long time I have experienced occasional crashes of CVS Emacs, 
usually during Tramp operations. I have four backtraces in case someone 
is interested, but I have not been able produce a test case. To me it 
looks as if GC is involved, but I am unexperienced with gdb. When Kim 
told he had fixed a bug involving GC and process output, it seemed at 
first very likely to be the cause of my troubles. However:

1. In one of the crashes Tramp was not involved.
2. CVS Emacs of today with Kim's fix, just crashed during a Tramp operation.

So now I don't know what to think.
Here is a backtrace from todays crash:

(gdb) run
Starting program: /home/lh/cvsroot/emacs/src/emacs

Program received signal SIGABRT, Aborted.
0x402ec781 in kill () from /lib/libc.so.6
(gdb) bt
#0  0x402ec781 in kill () from /lib/libc.so.6
#1  0x080dfe0a in abort () at emacs.c:433
#2  0x08128037 in mark_object (arg=1217041176) at alloc.c:5034
#3  0x0812809a in mark_object (arg=-1463681024) at alloc.c:5051
#4  0x08126b43 in mark_memory (start=0xbfffe070, end=0xbffff7e8)
   at alloc.c:3700
#5  0x08126f73 in mark_stack () at alloc.c:4055
#6  0x08127549 in Fgarbage_collect () at alloc.c:4429
#7  0x081627f5 in Fbyte_code (bytestr=1752418136, vector=-2006055672,
   maxdepth=53) at bytecode.c:522
#8  0x0813aec1 in funcall_lambda (fun=-2006055216, nargs=3,
   arg_vector=0xbfffe368) at eval.c:2913
#9  0x0813aa81 in Ffuncall (nargs=4, args=0xbfffe364) at eval.c:2783
#10 0x0813a3a5 in Fapply (nargs=3, args=0xbfffe418) at eval.c:2231
#11 0x0813a906 in Ffuncall (nargs=4, args=0xbfffe414) at eval.c:2707
#12 0x081629ec in Fbyte_code (bytestr=1752417784, vector=-2005715320,
   maxdepth=5) at bytecode.c:689
#13 0x0813aec1 in funcall_lambda (fun=-2006054856, nargs=3,
   arg_vector=0xbfffe548) at eval.c:2913
#14 0x0813aa81 in Ffuncall (nargs=4, args=0xbfffe544) at eval.c:2783
#15 0x0813a727 in call3 (fn=675593896, arg1=675187520, arg2=1751585648,
   arg3=675056464) at eval.c:2565
#16 0x08107d13 in Fexpand_file_name (name=1751585648,
   default_directory=675056464) at fileio.c:1705
#17 0x0813a9ad in Ffuncall (nargs=3, args=0xbfffe5f4) at eval.c:2729
#18 0x0813a3a5 in Fapply (nargs=2, args=0xbfffe6a8) at eval.c:2231
#19 0x0813a906 in Ffuncall (nargs=3, args=0xbfffe6a4) at eval.c:2707
#20 0x081629ec in Fbyte_code (bytestr=1752592784, vector=-2005500296,
   maxdepth=5) at bytecode.c:689
#21 0x0813aec1 in funcall_lambda (fun=-2005500152, nargs=3,
   arg_vector=0xbfffe7d8) at eval.c:2913
#22 0x0813aa81 in Ffuncall (nargs=4, args=0xbfffe7d4) at eval.c:2783
#23 0x0813a727 in call3 (fn=678851976, arg1=675187520, arg2=1751585648,
   arg3=675056464) at eval.c:2565
#24 0x08107d13 in Fexpand_file_name (name=1751585648,
   default_directory=675056464) at fileio.c:1705
#25 0x0810f5b0 in Fdirectory_files_and_attributes (directory=1751585648,
   full=675056464, match=675056464, nosort=675056512, id_format=675056464)
   at dired.c:383
#26 0x0813aa11 in Ffuncall (nargs=6, args=0xbfffe8c4) at eval.c:2759
#27 0x0813a3a5 in Fapply (nargs=2, args=0xbfffe988) at eval.c:2231
#28 0x0813a906 in Ffuncall (nargs=3, args=0xbfffe984) at eval.c:2707
#29 0x081629ec in Fbyte_code (bytestr=1752592784, vector=-2005500296,
   maxdepth=5) at bytecode.c:689
#30 0x0813aec1 in funcall_lambda (fun=-2005500152, nargs=6,
   arg_vector=0xbfffeab8) at eval.c:2913
#31 0x0813aa81 in Ffuncall (nargs=7, args=0xbfffeab4) at eval.c:2783
#32 0x0813a787 in call6 (fn=678851976, arg1=675173912, arg2=1751585648,
   arg3=675056464, arg4=675056464, arg5=675056512, arg6=675056464)
   at eval.c:2640
#33 0x0810f5fd in Fdirectory_files_and_attributes (directory=1757484384,
   full=675056464, match=675056464, nosort=675056512, id_format=675056464)
   at dired.c:389
#34 0x0813aa11 in Ffuncall (nargs=5, args=0xbfffeb94) at eval.c:2759
#35 0x081629ec in Fbyte_code (bytestr=1753402600, vector=-2004489696,
   maxdepth=9) at bytecode.c:689
#36 0x0813aec1 in funcall_lambda (fun=-2005624000, nargs=1,
   arg_vector=0xbfffecac) at eval.c:2913
#37 0x0813aa81 in Ffuncall (nargs=2, args=0xbfffeca8) at eval.c:2783
#38 0x081629ec in Fbyte_code (bytestr=1753388008, vector=-2004492704,
   maxdepth=3) at bytecode.c:689
#39 0x0813aec1 in funcall_lambda (fun=-2004860712, nargs=2,
   arg_vector=0xbfffeda8) at eval.c:2913
#40 0x0813aa81 in Ffuncall (nargs=3, args=0xbfffeda4) at eval.c:2783
#41 0x081629ec in Fbyte_code (bytestr=1753387640, vector=-2004626104,
   maxdepth=3) at bytecode.c:689
#42 0x0813aec1 in funcall_lambda (fun=-2004751064, nargs=0,
   arg_vector=0xbfffeea8) at eval.c:2913
#43 0x0813aa81 in Ffuncall (nargs=1, args=0xbfffeea4) at eval.c:2783
#44 0x081629ec in Fbyte_code (bytestr=1753387960, vector=-2004692136,
   maxdepth=7) at bytecode.c:689
#45 0x0813aec1 in funcall_lambda (fun=-2005043992, nargs=0,
   arg_vector=0xbfffefb8) at eval.c:2913
#46 0x0813aa81 in Ffuncall (nargs=1, args=0xbfffefb4) at eval.c:2783
#47 0x081629ec in Fbyte_code (bytestr=1753387448, vector=-2004623568,
   maxdepth=2) at bytecode.c:689
#48 0x0813aec1 in funcall_lambda (fun=-2004907320, nargs=0,
   arg_vector=0xbffff0b8) at eval.c:2913
#49 0x0813aa81 in Ffuncall (nargs=1, args=0xbffff0b4) at eval.c:2783
#50 0x081629ec in Fbyte_code (bytestr=1753223744, vector=-2004866968,
   maxdepth=3) at bytecode.c:689
#51 0x0813aec1 in funcall_lambda (fun=-2004917192, nargs=1,
   arg_vector=0xbffff1b8) at eval.c:2913
#52 0x0813aa81 in Ffuncall (nargs=2, args=0xbffff1b4) at eval.c:2783
#53 0x081629ec in Fbyte_code (bytestr=1753213760, vector=-2004869680,
   maxdepth=2) at bytecode.c:689
#54 0x0813aec1 in funcall_lambda (fun=-2004773840, nargs=0,
   arg_vector=0xbffff2d8) at eval.c:2913
#55 0x0813aa81 in Ffuncall (nargs=1, args=0xbffff2d4) at eval.c:2783
#56 0x0813a6b1 in apply1 (fn=679775736, arg=675056464) at eval.c:2476
#57 0x08136649 in Fcall_interactively (function=679775736,
   record_flag=675056464, keys=-2009241248) at callint.c:406
#58 0x080ecdc9 in Fcommand_execute (cmd=679775736, record_flag=675056464,
   keys=675056464, special=675056464) at keyboard.c:9670
#59 0x080e34ac in command_loop_1 () at keyboard.c:1727
#60 0x08138fad in internal_condition_case (bfun=0x80e27c0 <command_loop_1>,
   handlers=675117376, hfun=0x80e23c4 <cmd_error>) at eval.c:1333
#61 0x080e2688 in command_loop_2 () at keyboard.c:1264
#62 0x08138b25 in internal_catch (tag=675111408,
   func=0x80e2664 <command_loop_2>, arg=675056464) at eval.c:1094
#63 0x080e2633 in command_loop () at keyboard.c:1243
#64 0x080e2188 in recursive_edit_1 () at keyboard.c:959
#65 0x080e22b0 in Frecursive_edit () at keyboard.c:1015
#66 0x080e1122 in main (argc=1, argv=0xbffffa64) at emacs.c:1692
(gdb)