[PATCH] - fix compile warning: `found' might be used uninitialized in this function

[PATCH] - fix compile warning: `found' might be used uninitialized in this function

[roland]

Hello !

the attached patch should fix the following compile warning:

fs/block_dev.c: In function `bd_claim_by_kobject':
fs/block_dev.c:953: warning: `found' might be used uninitialized in this 
function

i`m an absolutely awful programmer , but feel free to comment, ignore or 
.... merge.

regards
Roland Kletzing


--- linux-2.6.20.3/fs/block_dev.c.orig  2007-03-22 00:07:49.270353920 +0100
+++ linux-2.6.20.3/fs/block_dev.c       2007-03-22 00:07:33.875694264 +0100
@@ -950,7 +950,7 @@
                                struct kobject *kobj)
 {
        int res;
-       struct bd_holder *bo, *found;
+       struct bd_holder *bo, *found = NULL;

        if (!kobj)
                return -EINVAL; 

Re: [PATCH] - fix compile warning: `found' might be used uninitialized in this function

[Johannes Weiner]

Hi,

On Thu, Mar 22, 2007 at 12:48:05AM +0100, roland wrote:
> fs/block_dev.c: In function `bd_claim_by_kobject':
> fs/block_dev.c:953: warning: `found' might be used uninitialized in this 
> function

found actually _is_ used uninitialized if the call to bd_claim() returns
anything but 0.  Thank you!

=Hannes

Re: [PATCH] - fix compile warning: `found' might be used uninitialized in this function

[Andrew Morton]

On Thu, 22 Mar 2007 00:56:08 +0100 Johannes Weiner <hannes-kernel@saeurebad.de> wrote:

> On Thu, Mar 22, 2007 at 12:48:05AM +0100, roland wrote:
> > fs/block_dev.c: In function `bd_claim_by_kobject':
> > fs/block_dev.c:953: warning: `found' might be used uninitialized in this 
> > function
> 
> found actually _is_ used uninitialized if the call to bd_claim() returns
> anything but 0.

No, it isn't.

        if (res || found)
                free_bd_holder(bo);

`found' won't be evaluated if res!=0.

The code in there is irksome - it'd be nice to find some way of
restructuring it to make it less obscure, and to kill that warning.

Re: [PATCH] - fix compile warning: `found' might be used uninitialized in this function

[Johannes Weiner]

Hi,

On Thu, Mar 22, 2007 at 12:45:40AM -0800, Andrew Morton wrote:
> > On Thu, Mar 22, 2007 at 12:48:05AM +0100, roland wrote:
> > > fs/block_dev.c: In function `bd_claim_by_kobject':
> > > fs/block_dev.c:953: warning: `found' might be used uninitialized in this 
> > > function
> > 
> > found actually _is_ used uninitialized if the call to bd_claim() returns
> > anything but 0.
> 
> No, it isn't.
> 
>         if (res || found)
>                 free_bd_holder(bo);
> 
> `found' won't be evaluated if res!=0.

Oh, thank you very much. So this warning is another gcc false-positive?

> The code in there is irksome - it'd be nice to find some way of
> restructuring it to make it less obscure, and to kill that warning.

Functionscope or filescope? ;)

=Hannes

Re: [PATCH] - fix compile warning: `found' might be used uninitialized in this function

[Johannes Weiner]

Hi,

On Thu, Mar 22, 2007 at 05:26:04PM +0100, Johannes Weiner wrote:
> > The code in there is irksome - it'd be nice to find some way of
> > restructuring it to make it less obscure, and to kill that warning.
> 
> Functionscope or filescope? ;)

Oh well... I think the latter.  I wil clean it up and send the patches
in several steps to seperate opticals from functionals.

=Hannes