[BUG] mode-line-process (Emacs 23)

[Nick Roberts]

Set debug-on-error to t.
Create a shell buffer, M-x shell.
Try to do list-buffers (C-x C-b):

Debugger entered--Lisp error: (error "Attempt to modify read-only object")
  format-mode-line((#(":%s" 0 3 (auto-composed t))) nil nil #<buffer *shell*>)
  list-buffers-noselect(nil)
  list-buffers(nil)
  call-interactively(list-buffers nil nil)

I always thought that mode-line-process had to be a string, but it looks like
it can be a list with a string element, but evidently not a propertized one.
The same error occurs when the compilation buffer is running.  I don't know
what auto-composed means.  It doesn't appear to be described in the manual.

--
Nick                                           http://www.inet.net.nz/~nickrob