On Tue, Feb 10, 2015 at 09:35:52PM -0200, Mauro Carvalho Chehab wrote: > Em Tue, 10 Feb 2015 12:57:24 +0200 > Antti Palosaari <crope@xxxxxx> escreveu: > > > On 02/09/2015 12:44 AM, Luis de Bethencourt wrote: > > > Cleaning the following compiler warning: > > > rtl2832.c:703:12: warning: 'tmp' may be used uninitialized in this function > > > > > > Even though it could never happen since if rtl2832_rd_demod_reg () doesn't set > > > tmp, this line would never run because we go to err. It is still nice to avoid > > > compiler warnings. > > > > > > Signed-off-by: Luis de Bethencourt <luis.bg@xxxxxxxxxxx> > > > --- > > > drivers/media/dvb-frontends/rtl2832.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/drivers/media/dvb-frontends/rtl2832.c b/drivers/media/dvb-frontends/rtl2832.c > > > index 5d2d8f4..ad36d1c 100644 > > > --- a/drivers/media/dvb-frontends/rtl2832.c > > > +++ b/drivers/media/dvb-frontends/rtl2832.c > > > @@ -685,7 +685,7 @@ static int rtl2832_read_status(struct dvb_frontend *fe, fe_status_t *status) > > > struct rtl2832_dev *dev = fe->demodulator_priv; > > > struct i2c_client *client = dev->client; > > > int ret; > > > - u32 tmp; > > > + u32 tmp = 0; > > > > > > dev_dbg(&client->dev, "\n"); > > > > I looked the code and I cannot see how it could used as uninitialized. > > Dunno how it could be fixed properly. > > > > Also, I think idiom to say compiler that variable could be uninitialized > > is to store its own value. But I am fine with zero initialization too. > > > > u32 tmp = tmp; > > Actually, the right way is to declare it as: > > u32 uninitialized_var(tmp) > > The syntax to suppress compiler warnings depends on the compiler: > > include/linux/compiler-clang.h:#define uninitialized_var(x) x = *(&(x)) > include/linux/compiler-gcc.h:#define uninitialized_var(x) x = x > > Also, using uninitialized_var() better documents it. > > Regards, > Mauro Hi Mauro, That is a way more elegant solution. Great! I will check out that compiler-clang header file, it's interesting. I just sent a revised patch using this :) Thanks, Luis -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
