[PATCH] iio: cdc: ad7746: Suppress false uninitialized value warning.

[PATCH] iio: cdc: ad7746: Suppress false uninitialized value warning.

[Jonathan Cameron]

From: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Fix warning:
drivers/iio/cdc/ad7746.c:336:14: warning: use of uninitialized value '<unknown>' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
reported on linux-next.  The compiler can't see into the implementation
of kstrtobool() to identify that the if (ret < 0) condition is
sufficient to detect cases where this parameter is not initialized.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/cdc/ad7746.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/cdc/ad7746.c b/drivers/iio/cdc/ad7746.c
index b266f5328140..5a3863bcaac9 100644
--- a/drivers/iio/cdc/ad7746.c
+++ b/drivers/iio/cdc/ad7746.c
@@ -333,7 +333,7 @@ static inline ssize_t ad7746_start_calib(struct device *dev,
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct ad7746_chip_info *chip = iio_priv(indio_dev);
 	int ret, timeout = 10;
-	bool doit;
+	bool doit = false;
 
 	ret = kstrtobool(buf, &doit);
 	if (ret < 0)
-- 
2.37.2

Re: [PATCH] iio: cdc: ad7746: Suppress false uninitialized value warning.

[Andy Shevchenko]

On Tue, Aug 30, 2022 at 10:10 PM Jonathan Cameron <jic23@kernel.org> wrote:
>
> From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
>
> Fix warning:
> drivers/iio/cdc/ad7746.c:336:14: warning: use of uninitialized value '<unknown>' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
> reported on linux-next.  The compiler can't see into the implementation
> of kstrtobool() to identify that the if (ret < 0) condition is
> sufficient to detect cases where this parameter is not initialized.

Sorry, but to me this sounds like a false positive that provokes
developer to add not only unneeded, but in some cases harmful code
(yes, there were cases in the history when preinitializing variable
with some value made a regression).
NAK from me (but you always may overrule as a maintainer :-).

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH] iio: cdc: ad7746: Suppress false uninitialized value warning.

[Jonathan Cameron]

On Tue, 30 Aug 2022 23:04:47 +0300
Andy Shevchenko <andy.shevchenko@gmail.com> wrote:

> On Tue, Aug 30, 2022 at 10:10 PM Jonathan Cameron <jic23@kernel.org> wrote:
> >
> > From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> >
> > Fix warning:
> > drivers/iio/cdc/ad7746.c:336:14: warning: use of uninitialized value '<unknown>' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
> > reported on linux-next.  The compiler can't see into the implementation
> > of kstrtobool() to identify that the if (ret < 0) condition is
> > sufficient to detect cases where this parameter is not initialized.  
> 
> Sorry, but to me this sounds like a false positive that provokes
> developer to add not only unneeded, but in some cases harmful code
> (yes, there were cases in the history when preinitializing variable
> with some value made a regression).
> NAK from me (but you always may overrule as a maintainer :-).
> 

I'm fine leaving it as is and exercising the delete key for any reports :)

Jonathan