[U-Boot] [PATCH 7/7] GCC4.6: Squash warning in cmd_mem.c

[Marek Vasut]

On Monday, September 26, 2011 08:29:22 PM Simon Glass wrote:
> Hi Merek,
> 
> On Mon, Sep 26, 2011 at 11:24 AM, Marek Vasut <marek.vasut at gmail.com> wrote:
> > On Monday, September 26, 2011 08:05:43 PM Simon Glass wrote:
> >> Hi Marek,
> >> 
> >> On Sun, Sep 25, 2011 at 5:26 PM, Marek Vasut <marek.vasut at gmail.com> wrote:
> >> > cmd_mem.c: In function ‘do_mem_loop’:
> >> > cmd_mem.c:474:25: warning: variable ‘junk’ set but not used
> >> > [-Wunused-but-set-variable]
> >> > 
> >> > The assigned variable can be removed because the pointers are volatile
> >> > so accesses to their addresses are always generated.
> >> > 
> >> > Signed-off-by: Marek Vasut <marek.vasut at gmail.com>
> >> > ---
> >> >  common/cmd_mem.c |    8 ++++----
> >> >  1 files changed, 4 insertions(+), 4 deletions(-)
> >> > 
> >> > diff --git a/common/cmd_mem.c b/common/cmd_mem.c
> >> > index 4daa1b3..e84cc4e 100644
> >> > --- a/common/cmd_mem.c
> >> > +++ b/common/cmd_mem.c
> >> > @@ -471,7 +471,7 @@ int do_mem_base (cmd_tbl_t *cmdtp, int flag, int
> >> > argc, char * const argv[])
> >> > 
> >> >  int do_mem_loop (cmd_tbl_t *cmdtp, int flag, int argc, char * const
> >> > argv[]) {
> >> > -       ulong   addr, length, i, junk;
> >> > +       ulong   addr, length, i;
> >> >        int     size;
> >> >        volatile uint   *longp;
> >> >        volatile ushort *shortp;
> >> > @@ -518,7 +518,7 @@ int do_mem_loop (cmd_tbl_t *cmdtp, int flag, int
> >> > argc, char * const argv[]) longp = (uint *)addr;
> >> >                        i = length;
> >> >                        while (i-- > 0)
> >> > -                               junk = *longp++;
> >> > +                               *longp++;
> >> >                }
> >> >        }
> >> >        if (size == 2) {
> >> > @@ -526,14 +526,14 @@ int do_mem_loop (cmd_tbl_t *cmdtp, int flag, int
> >> > argc, char * const argv[]) shortp = (ushort *)addr;
> >> >                        i = length;
> >> >                        while (i-- > 0)
> >> > -                               junk = *shortp++;
> >> > +                               *shortp++;
> >> >                }
> >> >        }
> >> >        for (;;) {
> >> >                cp = (u_char *)addr;
> >> >                i = length;
> >> >                while (i-- > 0)
> >> > -                       junk = *cp++;
> >> > +                       *cp++;
> >> >        }
> >> >  }
> >> 
> >> I checked the ARM assembler output and it looks fine.
> >> 
> >> Acked-by: Simon Glass <sjg at chromium.org>
> >> 
> >> Re the 'length == 1' case (above your patch) site, it is assigning to
> >> 'i' here. Could/should we remove that assignment also?
> > 
> > The loop below depends on that ... ?
> 
> Which loop? It doesn't look like the value of i is used?

i = length;
while (i-- > 0)

This loop

> 
> Regards,
> Simon
> 
> >> Regards,
> >> Simon
> >> 
> >> > --
> >> > 1.7.5.4
> >> > 
> >> > _______________________________________________
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