Re: [PATCH] mmc: fix card block compile warnings

[Ulf Hansson <ulf.hansson@stericsson.com>]

On 03/22/2012 08:35 AM, Linus Walleij wrote:
> I'm pretty tired of seeing these in my kernel compiles:
> drivers/mmc/card/block.c: In function ‘mmc_blk_issue_secdiscard_rq’:
> drivers/mmc/card/block.c:911:18: warning: ‘arg’ may be used uninitialized in this function [-Wuninitialized]
> drivers/mmc/card/block.c:910:6: warning: ‘nr’ may be used uninitialized in this function [-Wuninitialized]
> drivers/mmc/card/block.c:910:6: warning: ‘from’ may be used uninitialized in this function [-Wuninitialized]
>
> This patch marks the variables explicitly uninitialized as
> seems to be the intention, I can assure myself they are not
> actually uninitialized at use time by just reading the code.
>
> Signed-off-by: Linus Walleij<linus.walleij@linaro.org>
> ---
>   drivers/mmc/card/block.c |    4 +++-
>   1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
> index c6a383d..214ae68 100644
> --- a/drivers/mmc/card/block.c
> +++ b/drivers/mmc/card/block.c
> @@ -874,7 +874,9 @@ static int mmc_blk_issue_secdiscard_rq(struct mmc_queue *mq,
>   {
>   	struct mmc_blk_data *md = mq->data;
>   	struct mmc_card *card = md->queue.card;
> -	unsigned int from, nr, arg;
> +	unsigned int uninitialized_var(from);
> +	unsigned int uninitialized_var(nr);
> +	unsigned int uninitialized_var(arg);
>   	int err = 0, type = MMC_BLK_SECDISCARD;
>
>   	if (!(mmc_can_secure_erase_trim(card) || mmc_can_sanitize(card))) {

Is not the problem only related to the arg variable?

What about:
	unsigned int from, nr, arg = 0;

Yours!

Ulf Hansson