Why would you do this, rather than just delete the code you are removing?

> --- a/drivers/net/ppp/ppp_mppe.c
> +++ b/drivers/net/ppp/ppp_mppe.c
> @@ -521,11 +521,12 @@ mppe_decompress(void *arg, unsigned char
>                 state->sanity_errors += 100;
>                 goto sanity_error;
>         }
> -       if (state->stateful && ((ccount & 0xff) == 0xff) && !flushed) {
> +       if (state->stateful && ((ccount & 0xff) == 0xff) && !flushed)
> {/*
>                 printk(KERN_DEBUG "mppe_decompress[%d]: FLUSHED
> bit not set on "
>                        "flag packet!\n", state->unit);
>                 state->sanity_errors += 100;
> -               goto sanity_error;
> +               goto sanity_error;*/
> +                flushed = 1;
>         }