Re: [PATCH -next] powerpc/spufs: disp: Remove set but not used variable 'dummy'

Re: [PATCH -next] powerpc/spufs: disp: Remove set but not used variable 'dummy'

[Arnd Bergmann]

On Tue, Jun 1, 2021 at 10:43 AM Baokun Li <libaokun1@huawei.com> wrote:
>
> Fixes gcc '-Wunused-but-set-variable' warning:
>
> arch/powerpc/platforms/cell/spufs/switch.c: In function 'check_ppu_mb_stat':
> arch/powerpc/platforms/cell/spufs/switch.c:1660:6: warning:
> variable ‘dummy’ set but not used [-Wunused-but-set-variable]
>
> arch/powerpc/platforms/cell/spufs/switch.c: In function 'check_ppuint_mb_stat':
> arch/powerpc/platforms/cell/spufs/switch.c:1675:6: warning:
> variable ‘dummy’ set but not used [-Wunused-but-set-variable]
>
> It never used since introduction.
>
> Signed-off-by: Baokun Li <libaokun1@huawei.com>

I think in_be64() used to cause a different warning if the result was
ignored, but this is no longer the case.

Acked-by: Arnd Bergmann <arnd@arndb.de>

[PATCH -next] powerpc/spufs: disp: Remove set but not used variable 'dummy'

[Baokun Li]

Fixes gcc '-Wunused-but-set-variable' warning:

arch/powerpc/platforms/cell/spufs/switch.c: In function 'check_ppu_mb_stat':
arch/powerpc/platforms/cell/spufs/switch.c:1660:6: warning:
variable ‘dummy’ set but not used [-Wunused-but-set-variable]

arch/powerpc/platforms/cell/spufs/switch.c: In function 'check_ppuint_mb_stat':
arch/powerpc/platforms/cell/spufs/switch.c:1675:6: warning:
variable ‘dummy’ set but not used [-Wunused-but-set-variable]

It never used since introduction.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
---
 arch/powerpc/platforms/cell/spufs/switch.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/platforms/cell/spufs/switch.c b/arch/powerpc/platforms/cell/spufs/switch.c
index d56b4e3241cd..b41e81b22fdc 100644
--- a/arch/powerpc/platforms/cell/spufs/switch.c
+++ b/arch/powerpc/platforms/cell/spufs/switch.c
@@ -1657,14 +1657,13 @@ static inline void restore_spu_mb(struct spu_state *csa, struct spu *spu)
 static inline void check_ppu_mb_stat(struct spu_state *csa, struct spu *spu)
 {
 	struct spu_problem __iomem *prob = spu->problem;
-	u32 dummy = 0;
 
 	/* Restore, Step 66:
 	 *     If CSA.MB_Stat[P]=0 (mailbox empty) then
 	 *     read from the PPU_MB register.
 	 */
 	if ((csa->prob.mb_stat_R & 0xFF) == 0) {
-		dummy = in_be32(&prob->pu_mb_R);
+		in_be32(&prob->pu_mb_R);
 		eieio();
 	}
 }
@@ -1672,14 +1671,13 @@ static inline void check_ppu_mb_stat(struct spu_state *csa, struct spu *spu)
 static inline void check_ppuint_mb_stat(struct spu_state *csa, struct spu *spu)
 {
 	struct spu_priv2 __iomem *priv2 = spu->priv2;
-	u64 dummy = 0UL;
 
 	/* Restore, Step 66:
 	 *     If CSA.MB_Stat[I]=0 (mailbox empty) then
 	 *     read from the PPUINT_MB register.
 	 */
 	if ((csa->prob.mb_stat_R & 0xFF0000) == 0) {
-		dummy = in_be64(&priv2->puint_mb_R);
+		in_be64(&priv2->puint_mb_R);
 		eieio();
 		spu_int_stat_clear(spu, 2, CLASS2_ENABLE_MAILBOX_INTR);
 		eieio();
-- 
2.31.1

Re: [PATCH -next] powerpc/spufs: disp: Remove set but not used variable 'dummy'

[Michael Ellerman]

On Tue, 1 Jun 2021 16:51:27 +0800, Baokun Li wrote:
> Fixes gcc '-Wunused-but-set-variable' warning:
> 
> arch/powerpc/platforms/cell/spufs/switch.c: In function 'check_ppu_mb_stat':
> arch/powerpc/platforms/cell/spufs/switch.c:1660:6: warning:
> variable ‘dummy’ set but not used [-Wunused-but-set-variable]
> 
> arch/powerpc/platforms/cell/spufs/switch.c: In function 'check_ppuint_mb_stat':
> arch/powerpc/platforms/cell/spufs/switch.c:1675:6: warning:
> variable ‘dummy’ set but not used [-Wunused-but-set-variable]
> 
> [...]

Applied to powerpc/next.

[1/1] powerpc/spufs: disp: Remove set but not used variable 'dummy'
      https://git.kernel.org/powerpc/c/911bacda4658129bee039dc90fc0c3f193ee2695

cheers