[PATCH] eeepc-laptop: fix a Wuninitialized warning

[PATCH] eeepc-laptop: fix a Wuninitialized warning

[Chen Hanxiao]

Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
---
 drivers/platform/x86/eeepc-laptop.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c
index bd533c2..738fc0c 100644
--- a/drivers/platform/x86/eeepc-laptop.c
+++ b/drivers/platform/x86/eeepc-laptop.c
@@ -276,7 +276,7 @@ static ssize_t store_sys_acpi(struct device *dev, int cm,
 			      const char *buf, size_t count)
 {
 	struct eeepc_laptop *eeepc = dev_get_drvdata(dev);
-	int rv, value;
+	int rv, value = -1;
 
 	rv = parse_arg(buf, count, &value);
 	if (rv > 0)
-- 
1.9.0

Re: [PATCH] eeepc-laptop: fix a Wuninitialized warning

[Darren Hart]

On Fri, Sep 12, 2014 at 04:44:26PM +0800, Chen Hanxiao wrote:

Hi Chen,

I don't see such a warning with gcc 4.9.1. Which compiler are you using?

Please include these sorts of details (which compiler, etc.) when submitting
patches. I will never merge a patch without a complete commit message.


> Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
> ---
>  drivers/platform/x86/eeepc-laptop.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c
> index bd533c2..738fc0c 100644
> --- a/drivers/platform/x86/eeepc-laptop.c
> +++ b/drivers/platform/x86/eeepc-laptop.c
> @@ -276,7 +276,7 @@ static ssize_t store_sys_acpi(struct device *dev, int cm,
>  			      const char *buf, size_t count)
>  {
>  	struct eeepc_laptop *eeepc = dev_get_drvdata(dev);
> -	int rv, value;
> +	int rv, value = -1;
>  
>  	rv = parse_arg(buf, count, &value);

Inspecting the code, I don't see how this could possibly result in the use of an
uninitialized variable.

-- 
Darren Hart
Intel Open Source Technology Center

RE: [PATCH] eeepc-laptop: fix a Wuninitialized warning

[Chen, Hanxiao]

> -----Original Message-----
> From: Darren Hart [mailto:dvhart@infradead.org]
> On Fri, Sep 12, 2014 at 04:44:26PM +0800, Chen Hanxiao wrote:
> 
> Hi Chen,
> 
> I don't see such a warning with gcc 4.9.1. Which compiler are you using?
> 

I'm using gcc 4.8.2 on Fedora20.
Should we ignore the warning of old version of gcc?

If not, I'll resend this with a detail commit message.

Thanks for your help.

- Chen

> Please include these sorts of details (which compiler, etc.) when submitting
> patches. I will never merge a patch without a complete commit message.
> 
> 
> > Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
> > ---
> >  drivers/platform/x86/eeepc-laptop.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/platform/x86/eeepc-laptop.c
> b/drivers/platform/x86/eeepc-laptop.c
> > index bd533c2..738fc0c 100644
> > --- a/drivers/platform/x86/eeepc-laptop.c
> > +++ b/drivers/platform/x86/eeepc-laptop.c
> > @@ -276,7 +276,7 @@ static ssize_t store_sys_acpi(struct device *dev, int cm,
> >  			      const char *buf, size_t count)
> >  {
> >  	struct eeepc_laptop *eeepc = dev_get_drvdata(dev);
> > -	int rv, value;
> > +	int rv, value = -1;
> >
> >  	rv = parse_arg(buf, count, &value);
> 
> Inspecting the code, I don't see how this could possibly result in the use of
> an
> uninitialized variable.
> 
> --
> Darren Hart
> Intel Open Source Technology Center

Re: [PATCH] eeepc-laptop: fix a Wuninitialized warning

[Darren Hart]

On Mon, Sep 15, 2014 at 02:16:35AM +0000, Chen, Hanxiao wrote:
> 
> 
> > -----Original Message-----
> > From: Darren Hart [mailto:dvhart@infradead.org]
> > On Fri, Sep 12, 2014 at 04:44:26PM +0800, Chen Hanxiao wrote:
> > 
> > Hi Chen,
> > 
> > I don't see such a warning with gcc 4.9.1. Which compiler are you using?
> > 
> 
> I'm using gcc 4.8.2 on Fedora20.
> Should we ignore the warning of old version of gcc?
> 
> If not, I'll resend this with a detail commit message.

In my experience, we do not add workarounds for buggy compilers reporting bogus
unitialized variable warnings because those workarounds effectively mask
legitimate uninitialized variable cases.

Rafael, do you agree?

Thanks,

Darren


> 
> Thanks for your help.
> 
> - Chen
> 
> > Please include these sorts of details (which compiler, etc.) when submitting
> > patches. I will never merge a patch without a complete commit message.
> > 
> > 
> > > Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
> > > ---
> > >  drivers/platform/x86/eeepc-laptop.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/platform/x86/eeepc-laptop.c
> > b/drivers/platform/x86/eeepc-laptop.c
> > > index bd533c2..738fc0c 100644
> > > --- a/drivers/platform/x86/eeepc-laptop.c
> > > +++ b/drivers/platform/x86/eeepc-laptop.c
> > > @@ -276,7 +276,7 @@ static ssize_t store_sys_acpi(struct device *dev, int cm,
> > >  			      const char *buf, size_t count)
> > >  {
> > >  	struct eeepc_laptop *eeepc = dev_get_drvdata(dev);
> > > -	int rv, value;
> > > +	int rv, value = -1;
> > >
> > >  	rv = parse_arg(buf, count, &value);
> > 
> > Inspecting the code, I don't see how this could possibly result in the use of
> > an
> > uninitialized variable.
> > 
> > --
> > Darren Hart
> > Intel Open Source Technology Center

-- 
Darren Hart
Intel Open Source Technology Center