Re: [PATCH] char: fix sparse variable shadowing and int as NULL pointer in rocket.c

[Andrew Morton <akpm@linux-foundation.org>]

On Fri, 22 Feb 2008 09:46:59 -0800
Harvey Harrison <harvey.harrison@gmail.com> wrote:
>
> Subject: [PATCH] char: fix sparse variable shadowing and int as NULL pointer in rocket.c
>

Please try to make the patch titles big-endian.  This one could have been

char: rocket.c: fix sparse variable shadowing and int as NULL pointer

or even

rocket.c: fix sparse variable shadowing and int as NULL pointer

> Nested min() macros shadow _x, separate into two lines.
> drivers/char/rocket.c:451:7: warning: symbol '_x' shadows an earlier one
> drivers/char/rocket.c:451:7: originally declared here
> drivers/char/rocket.c:451:7: warning: symbol '_x' shadows an earlier one
> drivers/char/rocket.c:451:7: originally declared here
> drivers/char/rocket.c:451:7: warning: symbol '_y' shadows an earlier one
> drivers/char/rocket.c:451:7: originally declared here
> drivers/char/rocket.c:1754:7: warning: symbol '_x' shadows an earlier one
> drivers/char/rocket.c:1754:7: originally declared here
> drivers/char/rocket.c:1754:7: warning: symbol '_x' shadows an earlier one
> drivers/char/rocket.c:1754:7: originally declared here
> drivers/char/rocket.c:1754:7: warning: symbol '_y' shadows an earlier one
> drivers/char/rocket.c:1754:7: originally declared here
> drivers/char/rocket.c:1751:20: warning: Using plain integer as NULL pointer
> 

That's really a sparse glitch.  There's nothing we can sanely do about it.

> ---
>  drivers/char/rocket.c |    9 +++++----
>  1 files changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/char/rocket.c b/drivers/char/rocket.c
> index 72f2892..2778d64 100644
> --- a/drivers/char/rocket.c
> +++ b/drivers/char/rocket.c
> @@ -448,7 +448,8 @@ static void rp_do_transmit(struct r_port *info)
>  	while (1) {
>  		if (tty->stopped || tty->hw_stopped)
>  			break;
> -		c = min(info->xmit_fifo_room, min(info->xmit_cnt, XMIT_BUF_SIZE - info->xmit_tail));
> +		c = min(info->xmit_fifo_room, info->xmit_cnt);
> +		c = min(c, XMIT_BUF_SIZE - info->xmit_tail);

Apart from things like that.

Probably this code is cleaner than the old version so let's do it, but it
seems that we need a general fix.