Fork problem with hexchat if cygserver is running

[Ken Brown <kbrown at cornell dot edu>]

Roughly 1 out of 3 times that I try to use hexchat, I get a fork failure:

31143510 [main] hexchat 12392 dofork: child 12399 - died waiting for dll 
loading, errno 11

It only happens if cygserver is running.  I caught it under strace and saw the 
following:

    29   25558 [main] hexchat 12399 frok::child: hParent 0xAF0, load_dlls 1
    43   25601 [main] hexchat 12399 open_shared: name cygpid.12392, n 12392, 
shared 0x1100000 (wanted 0x0), h 0x10C, *m 6
    35   25636 [main] hexchat 12399 getpid: 12399 = getpid()
    65   25701 [main] hexchat 12399 transport_layer_pipes::connect: Try to 
connect to named pipe: \\.\pipe\cygwin-e022582115c10879-lpc
   363   26064 [main] hexchat 12399 C:\cygwin64\bin\hexchat.exe: *** fatal error 
in forked process - fixup_shms_after_fork: NtMapViewOfSection (0x7FF4EE130000), 
status 0xC0000018.  Terminating.

[status 0xC0000018 is STATUS_CONFLICTING_ADDRESSES.]

This was under cygwin-3.0.7-1.  It also happens with cygwin1.dll built from the 
current master branch, and it also happens with cygwin-3.0.6-1.  Not being 
familiar with this part of the Cygwin code, my first thought was to do a 
bisection.  But I haven't yet found a good revision to start with.  I will still 
try to do that, but in the meantime I thought I should report it.

Here are the reproduction instructions:

1. Start the cygserver service.

2. Start the X server.  (I do this by using the XWin Server shortcut, which 
basically just calls startxwin.)

3. Start xterm, and run 'hexchat &'.

4. Select the freenode network and click Connect.

Roughly 1 out of 3 times, the dofork error will print in the xterm window, and 
hexchat will hang at "Looking up chat.freenode.net".

Ken

P.S. File this under "No good deed goes unpunished."  I was trying to use 
hexchat to join #cygwin-developers.  I can still do that on 2 out of 3 attempts, 
but now I'm sidetracked trying to do a bisection.