bug#17526: 24.3.90; Crash in Cygwin-w32 build

bug#17526: 24.3.90; Crash in Cygwin-w32 build

[Ken Brown]

I just got a crash with the following backtrace:

#0  0x000007fefd5f3ca3 in KERNELBASE!DebugBreak ()
   from /c/Windows/system32/KERNELBASE.dll
#1  0x000000010061a344 in emacs_abort ()
    at /usr/src/debug/emacs-24.3.90-1/src/w32fns.c:8460
#2  0x000000010043616a in move_it_to (it=0x4284e0, to_charpos=-1, to_x=-1,
    to_y=-1, to_vpos=10, op=4)
    at /usr/src/debug/emacs-24.3.90-1/src/xdisp.c:9198
#3  0x0000000100436fc2 in move_it_by_lines (it=0x4284e0, dvpos=10)
    at /usr/src/debug/emacs-24.3.90-1/src/xdisp.c:9490
#4  0x000000010048972d in window_scroll_pixel_based (window=4312108109, n=10,
    whole=false, noerror=0) at /usr/src/debug/emacs-24.3.90-1/src/window.c:5021
#5  0x0000000100488e6e in window_scroll (window=4312108109, n=10, whole=false,
    noerror=0) at /usr/src/debug/emacs-24.3.90-1/src/window.c:4838
#6  0x000000010048a976 in scroll_command (n=40, direction=1)
    at /usr/src/debug/emacs-24.3.90-1/src/window.c:5395
#7  0x000000010048a9ad in Fscroll_up (arg=40)
    at /usr/src/debug/emacs-24.3.90-1/src/window.c:5410
#8  0x0000000100599b62 in Ffuncall (nargs=2, args=0x429400)
    at /usr/src/debug/emacs-24.3.90-1/src/eval.c:2815
#9  0x0000000100598538 in eval_sub (form=4303443726)
    at /usr/src/debug/emacs-24.3.90-1/src/eval.c:2157
#10 0x0000000100596576 in internal_lisp_condition_case (var=4305639474,
    bodyform=4303443726, handlers=4303443758)
    at /usr/src/debug/emacs-24.3.90-1/src/eval.c:1323
#11 0x00000001005de00c in exec_byte_code (bytestr=4303442833,
    vector=4303442869, maxdepth=36, args_template=4305639474, nargs=0, args=0x0)
    at /usr/src/debug/emacs-24.3.90-1/src/bytecode.c:1169
#12 0x000000010059a5a0 in funcall_lambda (fun=4303442781, nargs=1,
    arg_vector=0x1008153b5 <pure+1729173>)
    at /usr/src/debug/emacs-24.3.90-1/src/eval.c:3049
#13 0x0000000100599d77 in Ffuncall (nargs=2, args=0x429c70)
    at /usr/src/debug/emacs-24.3.90-1/src/eval.c:2864
#14 0x0000000100598b81 in Fapply (nargs=2, args=0x429c70)
    at /usr/src/debug/emacs-24.3.90-1/src/eval.c:2301
#15 0x000000010059945b in apply1 (fn=4314187618, arg=25779245142)
    at /usr/src/debug/emacs-24.3.90-1/src/eval.c:2588
#16 0x0000000100591c5d in Fcall_interactively (function=4314187618,
    record_flag=4305639474, keys=4305688189)
    at /usr/src/debug/emacs-24.3.90-1/src/callint.c:378
#17 0x0000000100599bb3 in Ffuncall (nargs=4, args=0x429ff8)
    at /usr/src/debug/emacs-24.3.90-1/src/eval.c:2822
#18 0x00000001005dcaa2 in exec_byte_code (bytestr=4302634489,
    vector=4302634525, maxdepth=52, args_template=4100, nargs=1, args=0x42a590)
    at /usr/src/debug/emacs-24.3.90-1/src/bytecode.c:919
#19 0x000000010059a286 in funcall_lambda (fun=4302634445, nargs=1,
    arg_vector=0x42a588) at /usr/src/debug/emacs-24.3.90-1/src/eval.c:2983
#20 0x0000000100599d77 in Ffuncall (nargs=2, args=0x42a580)
    at /usr/src/debug/emacs-24.3.90-1/src/eval.c:2864
#21 0x00000001005994ca in call1 (fn=4305696770, arg1=4314187618)
    at /usr/src/debug/emacs-24.3.90-1/src/eval.c:2614
#22 0x0000000100500128 in command_loop_1 ()
    at /usr/src/debug/emacs-24.3.90-1/src/keyboard.c:1556
#23 0x0000000100596707 in internal_condition_case (
    bfun=0x1004ff821 <command_loop_1>, handlers=4305705682,
    hfun=0x1004fef62 <cmd_error>)
    at /usr/src/debug/emacs-24.3.90-1/src/eval.c:1354
#24 0x00000001004ff4e5 in command_loop_2 (ignore=4305639474)
    at /usr/src/debug/emacs-24.3.90-1/src/keyboard.c:1174
#25 0x0000000100595e81 in internal_catch (tag=4305695746,
    func=0x1004ff4b3 <command_loop_2>, arg=4305639474)
    at /usr/src/debug/emacs-24.3.90-1/src/eval.c:1118
#26 0x00000001004ff474 in command_loop ()
    at /usr/src/debug/emacs-24.3.90-1/src/keyboard.c:1153
#27 0x00000001004feadf in recursive_edit_1 ()
    at /usr/src/debug/emacs-24.3.90-1/src/keyboard.c:777
#28 0x00000001004fec83 in Frecursive_edit ()
    at /usr/src/debug/emacs-24.3.90-1/src/keyboard.c:845
#29 0x00000001004fca49 in main (argc=1, argv=0x42ab30)
    at /usr/src/debug/emacs-24.3.90-1/src/emacs.c:1646

Lisp Backtrace:
"scroll-up" (0x429408)
"funcall" (0x429400)
"mwheel-scroll" (0x429c78)
"call-interactively" (0x42a000)
"command-execute" (0x42a588)

I still have the gdb session open if further information would be useful.

Ken

In GNU Emacs 24.3.90.1 (x86_64-unknown-cygwin)
 of 2014-05-03 on fiona
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure
 --srcdir=/home/kbrown/src/cygemacs/emacs-24.3.90-1.x86_64/src/emacs-24.3.90
 --prefix=/usr --exec-prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin
 --libexecdir=/usr/libexec --datadir=/usr/share --localstatedir=/var
 --sysconfdir=/etc --libdir=/usr/lib --datarootdir=/usr/share
 --docdir=/usr/share/doc/emacs --htmldir=/usr/share/doc/emacs/html -C
 --with-w32 'CFLAGS=-ggdb -O2 -pipe -Wimplicit-function-declaration -O0
 -fdebug-prefix-map=/home/kbrown/src/cygemacs/emacs-24.3.90-1.x86_64/build=/usr/src/debug/emacs-24.3.90-1
 -fdebug-prefix-map=/home/kbrown/src/cygemacs/emacs-24.3.90-1.x86_64/src/emacs-24.3.90=/usr/src/debug/emacs-24.3.90-1'
 CPPFLAGS= LDFLAGS=-Wl,--stack,0x400000'

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Fundamental

Minor modes in effect:
  show-paren-mode: t
  display-time-mode: t
  delete-selection-mode: t
  tooltip-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
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  temp-buffer-resize-mode: t
  buffer-read-only: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
C-x d s r c / e m <tab> e m <tab> s r <tab> <return> 
SPC SPC SPC SPC SPC SPC SPC SPC SPC v C-u 9 4 9 0 g 
<wheel-up> <wheel-down> <down-mouse-1> <mouse-1> <wheel-down> 
<double-wheel-down> <triple-wheel-down> <wheel-down> 
<wheel-up> <double-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<help-echo> <help-echo> q q C-h C-a M-x r e p o r t 
- e m <tab> <return>

Recent messages:
Loading help-at-pt...done
Loading paren...done
Loading /home/kbrown/emacs/.custom-24.el (source)...done
Loading /home/kbrown/emacs/cygwin-init.el (source)...done
For information about GNU Emacs and the GNU system, type C-h C-a.
mouse-2: visit this file in other window
View mode: type C-h for help, h for commands, q to quit.
Mark set
mouse-2: visit this file in other window
For information about GNU Emacs and the GNU system, type C-h C-a.

Load-path shadows:
None found.

Features:
(shadow gnus-util mail-extr emacsbug message idna cl-macs gv format-spec
rfc822 mml mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231
mailabbrev gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums
mm-util mail-prsvr mail-utils vc-bzr cc-langs cc-mode cc-fonts cc-guess
cc-menus cc-cmds cc-styles cc-align cc-engine cc-vars cc-defs view
server dired edmacro kmacro solar cal-dst planner-diary cl diary-lib
diary-loaddefs planner-publish muse-xml planner advice help-fns cal-menu
calendar cal-loaddefs sort muse-colors muse-latex muse-html
muse-xml-common cus-edit muse-publish muse-project muse-protocols
muse-regexps wid-edit cl-loaddefs cl-lib derived muse muse-nested-tags
muse-mode gap-mode-autoloads info easymenu muse-autoloads package
preview-latex tex-site auto-loads saveplace paren help-at-pt time delsel
cus-start cus-load time-date tooltip electric uniquify ediff-hook
vc-hooks lisp-float-type mwheel w32-common-fns disp-table w32-win
w32-vars tool-bar dnd fontset image regexp-opt fringe tabulated-list
newcomment lisp-mode prog-mode register page menu-bar rfn-eshadow timer
select scroll-bar mouse jit-lock font-lock syntax facemenu font-core
frame cham georgian utf-8-lang misc-lang vietnamese tibetan thai
tai-viet lao korean japanese hebrew greek romanian slovak czech european
ethiopic indian cyrillic chinese case-table epa-hook jka-cmpr-hook help
simple abbrev minibuffer nadvice loaddefs button faces cus-face macroexp
files text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote make-network-process
dbusbind gfilenotify w32 multi-tty emacs)

Memory information:
((conses 16 174489 9200)
 (symbols 48 26797 0)
 (miscs 40 119 178)
 (strings 32 37731 6072)
 (string-bytes 1 1158288)
 (vectors 16 18635)
 (vector-slots 8 467061 5782)
 (floats 8 438 80)
 (intervals 56 1208 0)
 (buffers 960 16))

bug#17526: 24.3.90; Crash in Cygwin-w32 build

[Eli Zaretskii]

> Date: Mon, 19 May 2014 08:30:49 -0400
> From: Ken Brown <kbrown@cornell.edu>
> 
> I just got a crash with the following backtrace:
> 
> #0  0x000007fefd5f3ca3 in KERNELBASE!DebugBreak ()
>    from /c/Windows/system32/KERNELBASE.dll
> #1  0x000000010061a344 in emacs_abort ()
>     at /usr/src/debug/emacs-24.3.90-1/src/w32fns.c:8460
> #2  0x000000010043616a in move_it_to (it=0x4284e0, to_charpos=-1, to_x=-1,
>     to_y=-1, to_vpos=10, op=4)
>     at /usr/src/debug/emacs-24.3.90-1/src/xdisp.c:9198
> #3  0x0000000100436fc2 in move_it_by_lines (it=0x4284e0, dvpos=10)
>     at /usr/src/debug/emacs-24.3.90-1/src/xdisp.c:9490

That's a weird crash.  Any chance of a reproducible recipe?

This is stock Emacs 24.3.90, with no C-level changes, right?

> I still have the gdb session open if further information would be useful.

Yes, please.  I'd like to see the values of these, in frame #2:

  skip
  it->current
  it->current_x
  it->current_y
  it->vpos

Also, what text is there in the window where the scroll command was
attempted, starting from the text position in it->current.pos.charpos
and for 10 screen lines down?

Thanks.

bug#17526: 24.3.90; Crash in Cygwin-w32 build

[Ken Brown]

On 5/19/2014 11:18 AM, Eli Zaretskii wrote:
>> Date: Mon, 19 May 2014 08:30:49 -0400
>> From: Ken Brown <kbrown@cornell.edu>
>>
>> I just got a crash with the following backtrace:
>>
>> #0  0x000007fefd5f3ca3 in KERNELBASE!DebugBreak ()
>>     from /c/Windows/system32/KERNELBASE.dll
>> #1  0x000000010061a344 in emacs_abort ()
>>      at /usr/src/debug/emacs-24.3.90-1/src/w32fns.c:8460
>> #2  0x000000010043616a in move_it_to (it=0x4284e0, to_charpos=-1, to_x=-1,
>>      to_y=-1, to_vpos=10, op=4)
>>      at /usr/src/debug/emacs-24.3.90-1/src/xdisp.c:9198
>> #3  0x0000000100436fc2 in move_it_by_lines (it=0x4284e0, dvpos=10)
>>      at /usr/src/debug/emacs-24.3.90-1/src/xdisp.c:9490
>
> That's a weird crash.  Any chance of a reproducible recipe?

No, I wasn't doing anything out of the ordinary -- just scrolling 
through a plain text file.  There have been other weird crashes reported 
for the Cygwin-w32 build, such as this one that was sent to the Cygwin 
mailing list this morning:

   https://cygwin.com/ml/cygwin/2014-05/msg00396.html

> This is stock Emacs 24.3.90, with no C-level changes, right?

Yes.

>> I still have the gdb session open if further information would be useful.
>
> Yes, please.  I'd like to see the values of these, in frame #2:
>
>    skip
>    it->current
>    it->current_x
>    it->current_y
>    it->vpos
>
> Also, what text is there in the window where the scroll command was
> attempted, starting from the text position in it->current.pos.charpos
> and for 10 screen lines down?

Unfortunately, my computer spontaneously rebooted while installing some 
software, without giving me a chance to say "reboot later".  So I have 
no information, and there's probably no more we can do with this bug.

Ken

bug#17526: 24.3.90; Crash in Cygwin-w32 build

[Eli Zaretskii]

> Date: Mon, 19 May 2014 15:19:24 -0400
> From: Ken Brown <kbrown@cornell.edu>
> CC: 17526@debbugs.gnu.org
> 
> On 5/19/2014 11:18 AM, Eli Zaretskii wrote:
> >> Date: Mon, 19 May 2014 08:30:49 -0400
> >> From: Ken Brown <kbrown@cornell.edu>
> >>
> >> I just got a crash with the following backtrace:
> >>
> >> #0  0x000007fefd5f3ca3 in KERNELBASE!DebugBreak ()
> >>     from /c/Windows/system32/KERNELBASE.dll
> >> #1  0x000000010061a344 in emacs_abort ()
> >>      at /usr/src/debug/emacs-24.3.90-1/src/w32fns.c:8460
> >> #2  0x000000010043616a in move_it_to (it=0x4284e0, to_charpos=-1, to_x=-1,
> >>      to_y=-1, to_vpos=10, op=4)
> >>      at /usr/src/debug/emacs-24.3.90-1/src/xdisp.c:9198
> >> #3  0x0000000100436fc2 in move_it_by_lines (it=0x4284e0, dvpos=10)
> >>      at /usr/src/debug/emacs-24.3.90-1/src/xdisp.c:9490
> >
> > That's a weird crash.  Any chance of a reproducible recipe?
> 
> No, I wasn't doing anything out of the ordinary -- just scrolling 
> through a plain text file.

Well, maybe try scrolling more than usual in the future, perhaps you
will hit it again.

> There have been other weird crashes reported 
> for the Cygwin-w32 build, such as this one that was sent to the Cygwin 
> mailing list this morning:
> 
>    https://cygwin.com/ml/cygwin/2014-05/msg00396.html

That crash makes no sense, arithcompare can only abort if its 3rd
argument is something other than the 6 enumeration values.  I suspect
that was an optimized build (although I see no "optimized out" values
in the backtrace).

> >    skip
> >    it->current
> >    it->current_x
> >    it->current_y
> >    it->vpos
> >
> > Also, what text is there in the window where the scroll command was
> > attempted, starting from the text position in it->current.pos.charpos
> > and for 10 screen lines down?
> 
> Unfortunately, my computer spontaneously rebooted while installing some 
> software, without giving me a chance to say "reboot later".  So I have 
> no information, and there's probably no more we can do with this bug.

Too bad.

bug#17526: 24.3.90; Crash in Cygwin-w32 build

[Ken Brown]

On 5/19/2014 3:39 PM, Eli Zaretskii wrote:
>> Date: Mon, 19 May 2014 15:19:24 -0400
>> From: Ken Brown <kbrown@cornell.edu>
>> CC: 17526@debbugs.gnu.org
>>
>> On 5/19/2014 11:18 AM, Eli Zaretskii wrote:
>>>> Date: Mon, 19 May 2014 08:30:49 -0400
>>>> From: Ken Brown <kbrown@cornell.edu>
>>>>
>>>> I just got a crash with the following backtrace:
>>>>
>>>> #0  0x000007fefd5f3ca3 in KERNELBASE!DebugBreak ()
>>>>      from /c/Windows/system32/KERNELBASE.dll
>>>> #1  0x000000010061a344 in emacs_abort ()
>>>>       at /usr/src/debug/emacs-24.3.90-1/src/w32fns.c:8460
>>>> #2  0x000000010043616a in move_it_to (it=0x4284e0, to_charpos=-1, to_x=-1,
>>>>       to_y=-1, to_vpos=10, op=4)
>>>>       at /usr/src/debug/emacs-24.3.90-1/src/xdisp.c:9198
>>>> #3  0x0000000100436fc2 in move_it_by_lines (it=0x4284e0, dvpos=10)
>>>>       at /usr/src/debug/emacs-24.3.90-1/src/xdisp.c:9490
>>>
>>> That's a weird crash.  Any chance of a reproducible recipe?
>>
>> No, I wasn't doing anything out of the ordinary -- just scrolling
>> through a plain text file.
>
> Well, maybe try scrolling more than usual in the future, perhaps you
> will hit it again.

I'll try.

>> There have been other weird crashes reported
>> for the Cygwin-w32 build, such as this one that was sent to the Cygwin
>> mailing list this morning:
>>
>>     https://cygwin.com/ml/cygwin/2014-05/msg00396.html
>
> That crash makes no sense, arithcompare can only abort if its 3rd
> argument is something other than the 6 enumeration values.  I suspect
> that was an optimized build (although I see no "optimized out" values
> in the backtrace).

No, it was an unoptimized build, but there's apparently something wrong 
with the backtrace.  I don't know what could cause that.

Ken

bug#17526: 24.3.90; Crash in Cygwin-w32 build

[Daniel Colascione]

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On 05/19/2014 12:39 PM, Eli Zaretskii wrote:
>> Date: Mon, 19 May 2014 15:19:24 -0400
>> From: Ken Brown <kbrown@cornell.edu>
>> CC: 17526@debbugs.gnu.org
>>
>> On 5/19/2014 11:18 AM, Eli Zaretskii wrote:
>>>> Date: Mon, 19 May 2014 08:30:49 -0400
>>>> From: Ken Brown <kbrown@cornell.edu>
>>>>
>>>> I just got a crash with the following backtrace:

There goes my BLODA theory (assuming you don't have any). These crashes
(including the indirect-variable one) are all seemingly impossible, but
if there were generalized random memory corruption, I'd expect to see
more severe effects. I have no idea what's wrong. Both trunk and
emacs-24 seem to be affected: did something change in the Cygwin DLL side?


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bug#17526: 24.3.90; Crash in Cygwin-w32 build

[Ken Brown]

On 5/19/2014 5:00 PM, Daniel Colascione wrote:
> On 05/19/2014 12:39 PM, Eli Zaretskii wrote:
>>> Date: Mon, 19 May 2014 15:19:24 -0400
>>> From: Ken Brown <kbrown@cornell.edu>
>>> CC: 17526@debbugs.gnu.org
>>>
>>> On 5/19/2014 11:18 AM, Eli Zaretskii wrote:
>>>>> Date: Mon, 19 May 2014 08:30:49 -0400
>>>>> From: Ken Brown <kbrown@cornell.edu>
>>>>>
>>>>> I just got a crash with the following backtrace:
>
> There goes my BLODA theory (assuming you don't have any). These crashes
> (including the indirect-variable one) are all seemingly impossible, but
> if there were generalized random memory corruption, I'd expect to see
> more severe effects. I have no idea what's wrong. Both trunk and
> emacs-24 seem to be affected: did something change in the Cygwin DLL side?

Not that I know of.  By the way, all these crashes that are being 
reported are in 64-bit Cygwin, FWIW.  So it may very well be a Cygwin 
problem rather than an emacs problem.

Do you have a 64-bit Cygwin installation on which you could try to 
reproduce this?  The crashes are seemingly random.  I've occasionally 
gotten a crash a few seconds after starting emacs, but other times I've 
run emacs for days without a problem.  So you might have to wait a long 
time.  Also, I don't always get a chance to attach gdb.  In other words, 
emacs just dies with a SEGV, but apparently without calling emacs_abort.

Ken

bug#17526: 24.3.90; Crash in Cygwin-w32 build

[Daniel Colascione]

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On 05/19/2014 02:45 PM, Ken Brown wrote:
> On 5/19/2014 5:00 PM, Daniel Colascione wrote:
>> On 05/19/2014 12:39 PM, Eli Zaretskii wrote:
>>>> Date: Mon, 19 May 2014 15:19:24 -0400
>>>> From: Ken Brown <kbrown@cornell.edu>
>>>> CC: 17526@debbugs.gnu.org
>>>>
>>>> On 5/19/2014 11:18 AM, Eli Zaretskii wrote:
>>>>>> Date: Mon, 19 May 2014 08:30:49 -0400
>>>>>> From: Ken Brown <kbrown@cornell.edu>
>>>>>>
>>>>>> I just got a crash with the following backtrace:
>>
>> There goes my BLODA theory (assuming you don't have any). These crashes
>> (including the indirect-variable one) are all seemingly impossible, but
>> if there were generalized random memory corruption, I'd expect to see
>> more severe effects. I have no idea what's wrong. Both trunk and
>> emacs-24 seem to be affected: did something change in the Cygwin DLL
>> side?
> 
> Not that I know of.  By the way, all these crashes that are being
> reported are in 64-bit Cygwin, FWIW.  So it may very well be a Cygwin
> problem rather than an emacs problem.
> 
> Do you have a 64-bit Cygwin installation on which you could try to
> reproduce this?  The crashes are seemingly random.  I've occasionally
> gotten a crash a few seconds after starting emacs, but other times I've
> run emacs for days without a problem.  So you might have to wait a long
> time.  Also, I don't always get a chance to attach gdb.  In other words,
> emacs just dies with a SEGV, but apparently without calling emacs_abort.

I don't, and it'll be at least a week or so before I'm able to set one
up. Nobody's reported crashes in the X11 Emacs? What about cygw32 run
with -nw?


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bug#17526: 24.3.90; Crash in Cygwin-w32 build

[Ken Brown]

On 5/19/2014 5:47 PM, Daniel Colascione wrote:
> On 05/19/2014 02:45 PM, Ken Brown wrote:
>> On 5/19/2014 5:00 PM, Daniel Colascione wrote:
>>> On 05/19/2014 12:39 PM, Eli Zaretskii wrote:
>>>>> Date: Mon, 19 May 2014 15:19:24 -0400
>>>>> From: Ken Brown <kbrown@cornell.edu>
>>>>> CC: 17526@debbugs.gnu.org
>>>>>
>>>>> On 5/19/2014 11:18 AM, Eli Zaretskii wrote:
>>>>>>> Date: Mon, 19 May 2014 08:30:49 -0400
>>>>>>> From: Ken Brown <kbrown@cornell.edu>
>>>>>>>
>>>>>>> I just got a crash with the following backtrace:
>>>
>>> There goes my BLODA theory (assuming you don't have any). These crashes
>>> (including the indirect-variable one) are all seemingly impossible, but
>>> if there were generalized random memory corruption, I'd expect to see
>>> more severe effects. I have no idea what's wrong. Both trunk and
>>> emacs-24 seem to be affected: did something change in the Cygwin DLL
>>> side?
>>
>> Not that I know of.  By the way, all these crashes that are being
>> reported are in 64-bit Cygwin, FWIW.  So it may very well be a Cygwin
>> problem rather than an emacs problem.
>>
>> Do you have a 64-bit Cygwin installation on which you could try to
>> reproduce this?  The crashes are seemingly random.  I've occasionally
>> gotten a crash a few seconds after starting emacs, but other times I've
>> run emacs for days without a problem.  So you might have to wait a long
>> time.  Also, I don't always get a chance to attach gdb.  In other words,
>> emacs just dies with a SEGV, but apparently without calling emacs_abort.
>
> I don't, and it'll be at least a week or so before I'm able to set one
> up. Nobody's reported crashes in the X11 Emacs? What about cygw32 run
> with -nw?

No, all the recent crash reports have been for cygw32.  But I doubt if 
anyone has run it with -nw.  I'll try that myself.

Ken

bug#17526: 24.3.90; Crash in Cygwin-w32 build

[Daniel Colascione]

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On 05/19/2014 06:49 PM, Ken Brown wrote:
> On 5/19/2014 5:47 PM, Daniel Colascione wrote:
>> On 05/19/2014 02:45 PM, Ken Brown wrote:
>>> On 5/19/2014 5:00 PM, Daniel Colascione wrote:
>>>> On 05/19/2014 12:39 PM, Eli Zaretskii wrote:
>>>>>> Date: Mon, 19 May 2014 15:19:24 -0400
>>>>>> From: Ken Brown <kbrown@cornell.edu>
>>>>>> CC: 17526@debbugs.gnu.org
>>>>>>
>>>>>> On 5/19/2014 11:18 AM, Eli Zaretskii wrote:
>>>>>>>> Date: Mon, 19 May 2014 08:30:49 -0400
>>>>>>>> From: Ken Brown <kbrown@cornell.edu>
>>>>>>>>
>>>>>>>> I just got a crash with the following backtrace:
>>>>
>>>> There goes my BLODA theory (assuming you don't have any). These crashes
>>>> (including the indirect-variable one) are all seemingly impossible, but
>>>> if there were generalized random memory corruption, I'd expect to see
>>>> more severe effects. I have no idea what's wrong. Both trunk and
>>>> emacs-24 seem to be affected: did something change in the Cygwin DLL
>>>> side?
>>>
>>> Not that I know of.  By the way, all these crashes that are being
>>> reported are in 64-bit Cygwin, FWIW.  So it may very well be a Cygwin
>>> problem rather than an emacs problem.
>>>
>>> Do you have a 64-bit Cygwin installation on which you could try to
>>> reproduce this?  The crashes are seemingly random.  I've occasionally
>>> gotten a crash a few seconds after starting emacs, but other times I've
>>> run emacs for days without a problem.  So you might have to wait a long
>>> time.  Also, I don't always get a chance to attach gdb.  In other words,
>>> emacs just dies with a SEGV, but apparently without calling emacs_abort.
>>
>> I don't, and it'll be at least a week or so before I'm able to set one
>> up. Nobody's reported crashes in the X11 Emacs? What about cygw32 run
>> with -nw?
> 
> No, all the recent crash reports have been for cygw32.  But I doubt if
> anyone has run it with -nw.  I'll try that myself.

Thanks. I'm just surprised that the crash is specific to the cygw32
configuration, that it happens nowhere near GUI code, and that both
regular Cygwin emacs and NT Emacs seem unaffected. Let's encourage
people to run --enable-checking for a while.


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bug#17526: 24.3.90; Crash in Cygwin-w32 build

[Eli Zaretskii]

> Date: Mon, 19 May 2014 17:45:41 -0400
> From: Ken Brown <kbrown@cornell.edu>
> CC: 17526@debbugs.gnu.org
> 
> Also, I don't always get a chance to attach gdb.  In other words,
> emacs just dies with a SEGV, but apparently without calling
> emacs_abort.

That might mean Emacs gets a fatal exception that gets handled by the
top-level exception handler.  Running under GDB to begin with should
avoid this nuisance (which AFAIK is new with Windows Vista and later).

bug#17526: 24.3.90; Crash in Cygwin-w32 build

[Eli Zaretskii]

> Date: Mon, 19 May 2014 08:30:49 -0400
> From: Ken Brown <kbrown@cornell.edu>
> 
> I just got a crash with the following backtrace:
> 
> #0  0x000007fefd5f3ca3 in KERNELBASE!DebugBreak ()
>    from /c/Windows/system32/KERNELBASE.dll
> #1  0x000000010061a344 in emacs_abort ()
>     at /usr/src/debug/emacs-24.3.90-1/src/w32fns.c:8460
> #2  0x000000010043616a in move_it_to (it=0x4284e0, to_charpos=-1, to_x=-1,
>     to_y=-1, to_vpos=10, op=4)
>     at /usr/src/debug/emacs-24.3.90-1/src/xdisp.c:9198
> #3  0x0000000100436fc2 in move_it_by_lines (it=0x4284e0, dvpos=10)
>     at /usr/src/debug/emacs-24.3.90-1/src/xdisp.c:9490
> #4  0x000000010048972d in window_scroll_pixel_based (window=4312108109, n=10,
>     whole=false, noerror=0) at /usr/src/debug/emacs-24.3.90-1/src/window.c:5021
> #5  0x0000000100488e6e in window_scroll (window=4312108109, n=10, whole=false,
>     noerror=0) at /usr/src/debug/emacs-24.3.90-1/src/window.c:4838
> #6  0x000000010048a976 in scroll_command (n=40, direction=1)
>     at /usr/src/debug/emacs-24.3.90-1/src/window.c:5395
> #7  0x000000010048a9ad in Fscroll_up (arg=40)
>     at /usr/src/debug/emacs-24.3.90-1/src/window.c:5410

I merged this with #17539, since they seem to be the same bug.