[PATCH 1/6] powerpc/powernv/smp: Fix spurious DBG() warning

[Joel Stanley]

On Tue, 4 Aug 2020 at 00:57, Oliver O'Halloran <oohall at gmail.com> wrote:
>
> When building with W=1 we get the following warning:
>
>  arch/powerpc/platforms/powernv/smp.c: In function ‘pnv_smp_cpu_kill_self’:
>  arch/powerpc/platforms/powernv/smp.c:276:16: error: suggest braces around
>         empty body in an ‘if’ statement [-Werror=empty-body]
>    276 |      cpu, srr1);
>        |                ^
>  cc1: all warnings being treated as errors
>
> The full context is this block:
>
>  if (srr1 && !generic_check_cpu_restart(cpu))
>         DBG("CPU%d Unexpected exit while offline srr1=%lx!\n",
>                         cpu, srr1);
>
> When building with DEBUG undefined DBG() expands to nothing and GCC emits
> the warning due to the lack of braces around an empty statement.
>
> Signed-off-by: Oliver O'Halloran <oohall at gmail.com>
> ---
> We could add the braces too. That might even be better since it's a multi-line
> if block even though it's only a single statement.

Or you could put it all on one line, now that our 120 line overlords
have taken over.

Reviewed-by: Joel Stanley <joel at jms.id.au>

Messy:

$ git grep "define DBG(" arch/powerpc/ |grep -v print
arch/powerpc/kernel/crash_dump.c:#define DBG(fmt...)
arch/powerpc/kernel/iommu.c:#define DBG(...)
arch/powerpc/kernel/legacy_serial.c:#define DBG(fmt...) do { } while(0)
arch/powerpc/kernel/prom.c:#define DBG(fmt...)
arch/powerpc/kernel/setup-common.c:#define DBG(fmt...)
arch/powerpc/kernel/setup_32.c:#define DBG(fmt...)
arch/powerpc/kernel/smp.c:#define DBG(fmt...)
arch/powerpc/kernel/vdso.c:#define DBG(fmt...)
arch/powerpc/kvm/book3s_hv_rm_xive.c:#define DBG(fmt...) do { } while(0)
arch/powerpc/mm/book3s64/hash_utils.c:#define DBG(fmt...)
arch/powerpc/platforms/83xx/mpc832x_mds.c:#define DBG(fmt...)
arch/powerpc/platforms/83xx/mpc832x_rdb.c:#define DBG(fmt...)
arch/powerpc/platforms/83xx/mpc836x_mds.c:#define DBG(fmt...)
arch/powerpc/platforms/85xx/mpc85xx_ds.c:#define DBG(fmt, args...)
arch/powerpc/platforms/85xx/mpc85xx_mds.c:#define DBG(fmt...)
arch/powerpc/platforms/85xx/mpc85xx_rdb.c:#define DBG(fmt, args...)
arch/powerpc/platforms/86xx/mpc86xx_hpcn.c:#define DBG(fmt...) do { } while(0)
arch/powerpc/platforms/cell/setup.c:#define DBG(fmt...)
arch/powerpc/platforms/cell/smp.c:#define DBG(fmt...)
arch/powerpc/platforms/embedded6xx/mpc7448_hpc2.c:#define DBG(fmt...)
do { } while(0)
arch/powerpc/platforms/maple/pci.c:#define DBG(x...)
arch/powerpc/platforms/maple/setup.c:#define DBG(fmt...)
arch/powerpc/platforms/maple/time.c:#define DBG(x...)
arch/powerpc/platforms/powermac/bootx_init.c:#define DBG(fmt...) do { } while(0)
arch/powerpc/platforms/powermac/feature.c:#define DBG(fmt...)
arch/powerpc/platforms/powermac/low_i2c.c:#define DBG(x...) do {\
arch/powerpc/platforms/powermac/low_i2c.c:#define DBG(x...)
arch/powerpc/platforms/powermac/nvram.c:#define DBG(x...)
arch/powerpc/platforms/powermac/pci.c:#define DBG(x...)
arch/powerpc/platforms/powermac/pfunc_base.c:#define DBG(fmt...)
arch/powerpc/platforms/powermac/pfunc_core.c:#define DBG(fmt...)
arch/powerpc/platforms/powermac/smp.c:#define DBG(fmt...)
arch/powerpc/platforms/powermac/time.c:#define DBG(x...)
arch/powerpc/platforms/powernv/smp.c:#define DBG(fmt...)
arch/powerpc/sysdev/dart_iommu.c:#define DBG(...)
arch/powerpc/sysdev/ge/ge_pic.c:#define DBG(fmt...) do { } while (0)
arch/powerpc/sysdev/mpic.c:#define DBG(fmt...)
arch/powerpc/sysdev/tsi108_dev.c:#define DBG(fmt...) do { } while(0)
arch/powerpc/sysdev/tsi108_pci.c:#define DBG(x...)


> ---
>  arch/powerpc/platforms/powernv/smp.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c
> index b2ba3e95bda7..bbf361f23ae8 100644
> --- a/arch/powerpc/platforms/powernv/smp.c
> +++ b/arch/powerpc/platforms/powernv/smp.c
> @@ -43,7 +43,7 @@
>  #include <asm/udbg.h>
>  #define DBG(fmt...) udbg_printf(fmt)
>  #else
> -#define DBG(fmt...)
> +#define DBG(fmt...) do { } while (0)
>  #endif
>
>  static void pnv_smp_setup_cpu(int cpu)
> --
> 2.26.2
>