Bug to fix!

[Richard Stallman]

[I sent this message a week ago but did not get a response.]

       Examining shell-mode-map shows that the repeated commands do appear
    bound to the same keys twice via list sharing.  You can see this for
    yourself by evaluating the following in *scratch*:

            (let ((print-circle t) (print-length nil)
                  (standard-output (current-buffer)))
              (prin1 shell-mode-map))

This is normal--it is part of the keymap parent mechanism.
shell-mode-map has comint-mode-map as its parent.
So the sub-keymap for C-c in shell-mode-map must also have,
as its parent, the sub-keymap for C-c in comint-mode-map.

So the right fix here is to change the code that generates
the table for C-h m so that it avoids generating duplicate
output in cases like this.

Would someone like to do that?