bug#13086: 24.2.50; Emacs seems to hang at w32proc.c:1126

[Eli Zaretskii <eliz@gnu.org>]

> Date: Thu, 06 Dec 2012 19:10:54 +0000
> From: Stephen Powell <stephen_powell@optusnet.com.au>
> CC: eggert@cs.ucla.edu, stephen_powell@optusnet.com.au, 13086@debbugs.gnu.org
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > I also found some potential problem in w32proc.c, and fixed that in
> > revision 111132 on the trunk.  Stephen, please try the latest code and
> > see if the problem persists.
> 
> OK, I tried that revision with the same problem.
> 
> I don't really know what I'm doing, but one odd thing I noticed while
> playing around with Paul's suggestion to set a breakpoint on
> delete_process:
> 
> 1. Set a breakpoint on process.c:808. Print p.pid and do a xbacktrace.
> 2. Run gnus.
> 3. Gnus uses imap.el to get mail from my host.
> 4. Imap.el calls delete-process from imap-close
> 
> $1 = 1356
> "delete-process" (0x88bf48)
> "imap-close" (0x88c248)
> "mail-source-fetch-imap" (0x88c584)
> 
> 5. Imap.el calls delete-process to delete the same pid from
> imap-sentinel
> 
> $2 = 1356
> "delete-process" (0x88b928)
> "imap-sentinel" (0x88bc24)
> "delete-process" (0x88bf48)
> "imap-close" (0x88c248)
> "mail-source-fetch-imap" (0x88c584)
> 
> 6. Let gnus sit for about a minute.  The error is signalled with the
> same pid
> 
> Breakpoint 1, terminate_due_to_signal (sig=22,
> backtrace_limit=2147483647) at emacs.c:314
> 314	  signal (sig, SIG_DFL);
> (gdb) up 2
> #2  0x0114a8db in get_child_status (child=1356, status=0x0, options=1,
> interruptible=false) at sysdep.c:294
> 294	      eassert (errno == EINTR);

What is the value of errno in frame #2?  Also, can you tell through
which line does waitpid exit in this case?