Re: [Outreachy kernel] [PATCH] iio: adc: Call uninitialized_var for raw_sample

[Greg KH <gregkh@linuxfoundation.org>]

On Thu, Mar 19, 2015 at 07:04:21PM +0530, Darshana Padmadas wrote:
> This patch calls uninitialized_var function for uninitialized
> variable raw_sample. This error was reported by the static
> analysis tool, cppcheck.
> 
> Signed-off-by: Darshana Padmadas <darshanapadmadas@gmail.com>
> ---
>  drivers/iio/adc/ad_sigma_delta.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/adc/ad_sigma_delta.c b/drivers/iio/adc/ad_sigma_delta.c
> index d10bd0c..f0bbf3c 100644
> --- a/drivers/iio/adc/ad_sigma_delta.c
> +++ b/drivers/iio/adc/ad_sigma_delta.c
> @@ -248,7 +248,8 @@ int ad_sigma_delta_single_conversion(struct iio_dev *indio_dev,
>  	const struct iio_chan_spec *chan, int *val)
>  {
>  	struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
> -	unsigned int sample, raw_sample;
> +	unsigned int sample;
> +	unsigned int uninitialized_var(raw_sample);

I don't understand, what exactly is this "fixing"?

And note, cppcheck is known to give you lots of false warnings / errors,
be very careful when using it.  Some kernel developers refuse to take
patches that mention it given that it has been wrong so many times in
the past.

thanks,

greg k-h