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

From: Andrew Morton
Date: Wed Feb 27 2008 - 18:30:40 EST


On Fri, 22 Feb 2008 09:46:59 -0800
Harvey Harrison <harvey.harrison@xxxxxxxxx> 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.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/