On 5/16/2014 4:06 PM, Ken Brown wrote:
> On 5/16/2014 1:50 PM, Ken Brown wrote:
>> This bug was reported in the Cygwin mailing list:
>>
>>    https://cygwin.com/ml/cygwin/2014-05/msg00303.html
>>
>> In a Cygwin terminal, do the following, where "emacs" denotes the cygw32
>> build of emacs (--with-w32).
>>
>> 1. $ emacs --daemon -Q
>> 2. $ emacsclient -c
>> 3. `C-x 5 0' in the client window to exit the frame.
>> 4. Repeat steps 2 and 3.
>> 5. Attempt to carry out steps 2 and 3 a third time.  The message
>> "Waiting for Emacs..." appears in the terminal, but no new frame opens.
>>
>> This problem is specific to the cygw32 build; it does not happen with
>> the X11 build of emacs on Cygwin.  It also doesn't happen if the server
>> is started via `M-x server-start' in an existing emacs.
>
> And it doesn't happen in emacs-24.3.  As soon as I have a chance, I'll
> do a bisection to see when it started.

Here's the culprit:

revno: 114710
committer: Dmitry Antipov <dmantipov@yandex.ru>
branch nick: trunk
timestamp: Fri 2013-10-18 16:57:44 +0400
message:
   Remove port-specific display name lists to avoid extra
   complexity and data duplication with display info lists.
[...]
   * w32term.h (w32_display_name_list): Remove declaration.
   * w32term.c (w32_display_name_list): Remove.
   (w32_initialize_display_info, x_delete_display, syms_of_w32term):
   Adjust users.
   * w32fns.c (x_display_info_for_name, Fx_display_list):
   Likewise.  Use x_display_list where appropriate.
[...]

The attached patch applied to the emacs-24 branch reverts these changes 
and fixes the problem.  This is presumably no the "right" fix.  Note, 
however, that Dimity's commit introduced a "FIXME" into x_delete_display 
in w32term.c.  Maybe that's the issue.

Ken