Re: [PATCH 5/5]scsi:hosts.c Fix warning: variable 'rval' set but not used

[James Bottomley <James.Bottomley@suse.de>]

On Wed, 2010-06-16 at 09:00 -0700, Justin P. Mattock wrote:
> On 06/16/2010 08:34 AM, James Bottomley wrote:
> > On Tue, 2010-06-15 at 22:33 -0700, Justin P. Mattock wrote:
> >> The below patch fixes a warning message generated by gcc 4.6.0
> >>    CC      drivers/scsi/hosts.o
> >> drivers/scsi/hosts.c: In function 'scsi_host_alloc':
> >> drivers/scsi/hosts.c:328:6: warning: variable 'rval' set but not used
> >>
> >>   Signed-off-by: Justin P. Mattock<justinmattock@gmail.com>
> >>
> >> ---
> >>   drivers/scsi/hosts.c |    2 --
> >>   1 files changed, 0 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
> >> index 6660fa9..00fd6a4 100644
> >> --- a/drivers/scsi/hosts.c
> >> +++ b/drivers/scsi/hosts.c
> >> @@ -325,7 +325,6 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
> >>   {
> >>   	struct Scsi_Host *shost;
> >>   	gfp_t gfp_mask = GFP_KERNEL;
> >> -	int rval;
> >>
> >>   	if (sht->unchecked_isa_dma&&  privsize)
> >>   		gfp_mask |= __GFP_DMA;
> >> @@ -420,7 +419,6 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
> >>   	shost->ehandler = kthread_run(scsi_error_handler, shost,
> >>   			"scsi_eh_%d", shost->host_no);
> >>   	if (IS_ERR(shost->ehandler)) {
> >> -		rval = PTR_ERR(shost->ehandler);
> >>   		goto fail_kfree;
> >>   	}
> >
> > For future reference, this is less stylistically acceptable C: you've
> > reduced the if clause to a single statement, so the braces need
> > removing.
> >
> > However, I don't think we should be ignoring the fact that the eh thread
> > failed to spawn, so I think some type of printed warning (giving the
> > error code) would be a much more appropriate replacement.
> >
> > James
> >
> >
> >
> 
> 
> o.k. I'll give a try at that.. as a  test I did this(below) seemed to 
> compile clean, but not sure if this is what you're asking for though:
> 
> 
>  From 8a4d6e793e0f92d180a6f48c53bbf00d2751ad01 Mon Sep 17 00:00:00 2001
> From: Justin P. Mattock <justinmattock@gmail.com>
> Date: Wed, 16 Jun 2010 08:58:13 -0700
> Subject: [PATCH] test
>   Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
> 
> ---
>   drivers/scsi/hosts.c |    3 +--
>   1 files changed, 1 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
> index 6660fa9..8d98a46 100644
> --- a/drivers/scsi/hosts.c
> +++ b/drivers/scsi/hosts.c
> @@ -325,7 +325,6 @@ struct Scsi_Host *scsi_host_alloc(struct 
> scsi_host_template *sht, int privsize)
>   {
>   	struct Scsi_Host *shost;
>   	gfp_t gfp_mask = GFP_KERNEL;
> -	int rval;
> 
>   	if (sht->unchecked_isa_dma && privsize)
>   		gfp_mask |= __GFP_DMA;
> @@ -420,7 +419,7 @@ struct Scsi_Host *scsi_host_alloc(struct 
> scsi_host_template *sht, int privsize)
>   	shost->ehandler = kthread_run(scsi_error_handler, shost,
>   			"scsi_eh_%d", shost->host_no);
>   	if (IS_ERR(shost->ehandler)) {
> -		rval = PTR_ERR(shost->ehandler);
> +		printk(KERN_WARNING "test.....\n")

Erm, well, as I said, error code and the fact that the thread failed to
start, so more

printk(KERN_WARNING "scsi%d: error handler thread failed to spawn, error
= %d\n", host->host_no, PTR_ERR(shost->ehandler));

James