bug#5061: I have found the location of this bug...

[Michael Welsh Duggan <md5i@md5i.com>]

Stefan Monnier <monnier@IRO.UMontreal.CA> writes:

>> This bug is due to the Stefan Monnier's commit on 2009-10-31.  In
>> particular, reverting the following diff solves this problem:
>
> Great, I've installed the fix below which should do it right.

This does indeed solve the problem.

> --- lisp/progmodes/gud.el	11 Nov 2009 05:49:14 -0000	1.174
> +++ lisp/progmodes/gud.el	27 Nov 2009 19:29:54 -0000
> @@ -2832,6 +2832,7 @@
>      (or proc (error "Current buffer has no process"))
>      ;; Arrange for the current prompt to get deleted.
>      (with-current-buffer gud-comint-buffer
> +      (save-excursion
>        (save-restriction
>  	(widen)
>  	(if (marker-position gud-delete-prompt-marker)
> @@ -2843,7 +2844,7 @@
>  	    (set-marker gud-delete-prompt-marker (point)))
>  	(if (eq gud-minor-mode 'gdbmi)
>  	    (apply comint-input-sender (list proc command))
> -	  (process-send-string proc (concat command "\n")))))))
> +            (process-send-string proc (concat command "\n"))))))))
>  
>  (defun gud-refresh (&optional arg)
>    "Fix up a possibly garbled display, and redraw the arrow."

-- 
Michael Welsh Duggan
(md5i@md5i.com)