Re: [PATCH] powerpc: sstep: Mark variable `rc` as unused in function 'analyse_instr'

From: Mathieu Malaterre
Date: Tue Mar 12 2019 - 17:13:14 EST


On Tue, Mar 12, 2019 at 9:56 PM Christophe Leroy
<christophe.leroy@xxxxxx> wrote:
>
>
>
> Le 12/03/2019 Ã 21:20, Mathieu Malaterre a Ãcrit :
> > Add gcc attribute unused for `rc` variable.
> >
> > Fix warnings treated as errors with W=1:
> >
> > arch/powerpc/lib/sstep.c:1172:31: error: variable 'rc' set but not used [-Werror=unused-but-set-variable]
> >
> > Signed-off-by: Mathieu Malaterre <malat@xxxxxxxxxx>
> > ---
> > arch/powerpc/lib/sstep.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
> > index 3d33fb509ef4..32d092f62ae0 100644
> > --- a/arch/powerpc/lib/sstep.c
> > +++ b/arch/powerpc/lib/sstep.c
> > @@ -1169,7 +1169,7 @@ static nokprobe_inline int trap_compare(long v1, long v2)
> > int analyse_instr(struct instruction_op *op, const struct pt_regs *regs,
> > unsigned int instr)
> > {
> > - unsigned int opcode, ra, rb, rc, rd, spr, u;
> > + unsigned int opcode, ra, rb, rc __maybe_unused, rd, spr, u;
>
> I think it would be better to enclose 'rc' inside a #ifdef CONFIG_PPC64

Hum odd, I would have bet you would have suggested me to use
IS_ENABLED with some crazy scheme (I was not able to mix it with the
switch case nicely).

Anyway I'll try your suggestion and post a v2.

> Christophe
>
> > unsigned long int imm;
> > unsigned long int val, val2;
> > unsigned int mb, me, sh;
> >