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

Marek Vasut
2011-09-26T18:24:57Z

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@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@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@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 ... ?

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