Shell in Cygwin Emacs doesn't source .bashrc

[David M. Karr]

I'm on a new Windows Seven box, with the latest released Cygwin and 
Cygwin Emacs. I copied over my .emacs file from an older Cygwin 
installation on a Windows XP box.

On the old WinXP box, after I start Emacs and execute "shell", it 
appears to properly execute my .bashrc, setting my PS1 and putting me in 
my home directory.

On the new box, when I execute "shell", the prompt isn't set to my PS1 
value, and the current directory is "/usr/bin".

If I execute "bash" at that point, and then "cd", I'm where I should be, 
and with my environment set up.

Something obviously changed between the older installation and the 
latest, which my older .emacs isn't dealing with properly.

I don't currently have a "$HOME/.emacs_bash" file. I don't know if I 
need it.

I start Emacs with the following shortcut command line:

     C:\cygwin\bin\run.exe -p /usr/bin emacs-X11.exe -display 127.0.0.1:0.0

I have a feeling this line might be the problem.  Do I have to make this 
run "bash" instead, and have that run Emacs?

If it matters, here is my current shell-mode-hook function, which I set 
to "shell-mode-hook" in a "custom-set-variables" block:
---------------------------
(defun my-shell-mode-hook ()
  (add-hook 'comint-output-filter-functions
        'comint-watch-for-password-prompt nil t)
  (setq explicit-shell-file-name "bash")
  (setq shell-file-name explicit-shell-file-name)
  (ansi-color-for-comint-mode-on)
  (setq shell-prompt-pattern "^\[[A-z0-9]+:[A-z0-9/]+\] ")
  (local-set-key "\C-xs" 'cycle-go-shell)
  (local-set-key "\C-xS" 'cycle-find-shell-or-shells-buffer-list)
  (local-set-key "\C-j" 'lfd-send-input)
  (local-set-key [f5] 'comint-previous-matching-input-from-input)
  (local-set-key [f12] 'compilation-shell-minor-mode)
  )
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