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

[Eli Zaretskii]

> Date: Thu, 06 Dec 2012 20:17:45 +0000
> From: Stephen Powell <stephen_powell@optusnet.com.au>
> CC: stephen_powell@optusnet.com.au, 13086@debbugs.gnu.org, eggert@cs.ucla.edu
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> Answering your first mail:
> 
> > What is the value of errno in frame #2?
> 
> (gdb) p errno
> $25 = 10

That's ECHILD.

> > Also, can you tell through which line does waitpid exit in this case?
> 
> Breakpoint 5, waitpid (pid=4860, status=0x0, options=1) at w32proc.c:1190
> 1190            return -1;
> $24 = 4860

It seems we are looking for a process that is not on our list of
watched child processes.  How could that happen?

Can you look at the contents of the child_procs array, and see if the
process we are looking for is there?  Also, what is the value of
child_proc_count when waitpid is called?

If the above doesn't show the light, can you please compile w32proc.c
with -DFULL_DEBUG, and see what Emacs says about processes it launches
and reaps when you run Emacs under GDB?

Thanks.