Re: [PATCH 3/3] xen p2m: annotate variable which appears unused

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Fri, Feb 11, 2011 at 03:23:58PM +0000, Ian Campbell wrote:
>  CC      arch/x86/xen/p2m.o
> arch/x86/xen/p2m.c: In function 'm2p_remove_override':
> arch/x86/xen/p2m.c:460: warning: 'address' may be used uninitialized in this function
> arch/x86/xen/p2m.c: In function 'm2p_add_override':
> arch/x86/xen/p2m.c:426: warning: 'address' may be used uninitialized in this function

Thanks for  doing those. I've been seeing them for weeks now and just never
got off to fixing them.
> 
> In actual fact address is inialised in one "if (!PageHighMem(page))"
> statement and used in a second and so is always initialised before
> use.
> 
> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
> ---
>  arch/x86/xen/p2m.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c
> index 53fe9fc..3720efa 100644
> --- a/arch/x86/xen/p2m.c
> +++ b/arch/x86/xen/p2m.c
> @@ -421,7 +421,7 @@ int m2p_add_override(unsigned long mfn, struct page *page)
>  {
>  	unsigned long flags;
>  	unsigned long pfn;
> -	unsigned long address;
> +	unsigned long uninitialized_var(address);
>  	unsigned level;
>  	pte_t *ptep = NULL;
>  
> @@ -455,7 +455,7 @@ int m2p_remove_override(struct page *page)
>  	unsigned long flags;
>  	unsigned long mfn;
>  	unsigned long pfn;
> -	unsigned long address;
> +	unsigned long uninitialized_var(address);
>  	unsigned level;
>  	pte_t *ptep = NULL;
>  
> -- 
> 1.5.6.5