[07/10] spi: davinci: Remove uninitialized_var() usage
diff mbox series

Message ID 20200603233203.1695403-8-keescook@chromium.org
State New
Headers show
Series
  • Remove uninitialized_var() macro
Related show

Commit Message

Kees Cook June 3, 2020, 11:32 p.m. UTC
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings (e.g.
"unused variable"). If the compiler thinks it is uninitialized, either
simply initialize the variable or make compiler changes. As a precursor
to removing[2] this[3] macro[4], just remove this variable since it was
actually unused:

drivers/spi/spi-davinci.c: In function ‘davinci_spi_bufs’:
drivers/spi/spi-davinci.c:579:11: warning: unused variable ‘rx_buf_count’ [-Wunused-variable]
  579 |  unsigned rx_buf_count;
      |           ^~~~~~~~~~~~

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Signed-off-by: Kees Cook <keescook@chromium.org>
---
 drivers/spi/spi-davinci.c | 1 -
 1 file changed, 1 deletion(-)

Comments

Nick Desaulniers June 4, 2020, 7:40 p.m. UTC | #1
On Wed, Jun 3, 2020 at 4:32 PM Kees Cook <keescook@chromium.org> wrote:
>
> Using uninitialized_var() is dangerous as it papers over real bugs[1]
> (or can in the future), and suppresses unrelated compiler warnings (e.g.
> "unused variable"). If the compiler thinks it is uninitialized, either
> simply initialize the variable or make compiler changes. As a precursor
> to removing[2] this[3] macro[4], just remove this variable since it was
> actually unused:
>
> drivers/spi/spi-davinci.c: In function ‘davinci_spi_bufs’:
> drivers/spi/spi-davinci.c:579:11: warning: unused variable ‘rx_buf_count’ [-Wunused-variable]
>   579 |  unsigned rx_buf_count;
>       |           ^~~~~~~~~~~~
>
> [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
> [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
> [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
> [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/
>
> Signed-off-by: Kees Cook <keescook@chromium.org>

Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Fixes 048177ce3b39 ("spi: spi-davinci: convert to DMA engine API")

> ---
>  drivers/spi/spi-davinci.c | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c
> index f71c497393a6..f50c0c79cbdf 100644
> --- a/drivers/spi/spi-davinci.c
> +++ b/drivers/spi/spi-davinci.c
> @@ -576,7 +576,6 @@ static int davinci_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
>         u32 errors = 0;
>         struct davinci_spi_config *spicfg;
>         struct davinci_spi_platform_data *pdata;
> -       unsigned uninitialized_var(rx_buf_count);
>
>         dspi = spi_master_get_devdata(spi->master);
>         pdata = &dspi->pdata;
> --
> 2.25.1
>
> --
> You received this message because you are subscribed to the Google Groups "Clang Built Linux" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to clang-built-linux+unsubscribe@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/clang-built-linux/20200603233203.1695403-8-keescook%40chromium.org.

Patch
diff mbox series

diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c
index f71c497393a6..f50c0c79cbdf 100644
--- a/drivers/spi/spi-davinci.c
+++ b/drivers/spi/spi-davinci.c
@@ -576,7 +576,6 @@  static int davinci_spi_bufs(struct spi_device *spi, struct spi_transfer *t)
 	u32 errors = 0;
 	struct davinci_spi_config *spicfg;
 	struct davinci_spi_platform_data *pdata;
-	unsigned uninitialized_var(rx_buf_count);
 
 	dspi = spi_master_get_devdata(spi->master);
 	pdata = &dspi->pdata;