Re: crash on latest cygwin snapshot

[Corinna Vinschen <corinna-cygwin at cygwin dot com>]

On Jun 25 10:37, marco atzeri wrote:
> On 6/25/2012 10:05 AM, Corinna Vinschen wrote:
> >On Jun 25 09:34, marco atzeri wrote:
> >>I tried to strace but it produces an enormous amount of data
> >>
> >>$ ls -sh1  xprobe_comp.strace*
> >>330M xprobe_comp.strace_fail
> >>761M xprobe_comp.strace_good
> >>
> >>and there is no guarantee that the root cause is traced.
> >
> >Does the failing strace contain a line like this?
> >
> >   --- Process 3708, exception C0000094 at 00401198
> >
> >If so, it might give a clue.  There's a chance that an exception
> >generates another exception, so you might have more than one such
> >line.  The first one rules.  Did you try from CVS again with cgf's
> >latest patch?
> >
> >
> >Corinna
> >
> 
> Hi Corinna,
> Tested up to
> http://cygwin.com/ml/cygwin-cvs/2012-q2/msg00129.html

What about http://cygwin.com/ml/cygwin-cvs/2012-q2/msg00130.html ?

> There are no exceptions on the strace.
> 
> The last portion, ~ 500 lines, of strace is available here:
> http://matzeri.altervista.org/works/atlas/
> 
> together with the equivalent area of the good strace (~ 1000 lines).
> 
> A normal exception should kill just the running process, while
> I see that  xprobe_comp, bash, mintty are killed and
> also others bash and mintty processes are taking down.

Really all processes or just all processes in the same terminal window?
If it's the latter, the problem may be triggered by xprobe_comp, but
it would really occur in mintty.  Here's an interesting snippet from the
failing strace:

  414 195741371 [main] xprobe_comp 1084 fhandler_pty_slave::write: pty0, write(40B7E7, 6)
   47 195741418 [main] xprobe_comp 1084 fhandler_pty_slave::write: (648): pty output_mutex (0xCC): waiting -1 ms
   46 195741464 [main] xprobe_comp 1084 fhandler_pty_slave::write: (648): pty output_mutex: acquired
   50 195741514 [main] xprobe_comp 1084 fhandler_pty_slave::write: WriteFile failed, Win32 error 232
   45 195741559 [main] xprobe_comp 1084 seterrno_from_win_error: /pub/cygwin/cvs/src_new/winsup/cygwin/fhandler_tty.cc:676 windows error 1117
   47 195741606 [main] xprobe_comp 1084 geterrno_from_win_error: windows error 1117 == errno 5

So a WriteFile to the slave side of the pty returns with ERROR_NO_DATA
which means the pipe has been closed on the other end.  The other end is
the master, which should be mintty here.  The strace doesn't cover
mintty so there's no way to see what happens in there.


Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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