# Re: \[PATCH\] powerpc: platforms: cell: pervasive: fix clang -Wimplicit-fallthrough

- From: Michael Ellerman \<mpe@ellerman.id.au\>
- Date: 2021-12-09 06:40:32 
- List: linuxppc-dev
- Page: https://ratatoskr.run/linuxppc-dev/2021/12/1602076
- Thread: https://ratatoskr.run/linuxppc-dev/2021/12/1599591/t.md

```text
Anders Roxell [ref] writes:
> Clang warns:
>
> arch/powerpc/platforms/cell/pervasive.c:81:2: error: unannotated fall-through between switch labels [-Werror,-Wimplicit-fallthrough]
>         case SRR1_WAKEEE:
>         ^
> arch/powerpc/platforms/cell/pervasive.c:81:2: note: insert 'break;' to avoid fall-through
>         case SRR1_WAKEEE:
>         ^
>         break;
> 1 error generated.
>
> Clang is more pedantic than GCC, which does not warn when failing
> through to a case that is just break or return. Clang's version
> is more in line with the kernel's own stance in deprecated.rst.
> Add athe missing break to silence the warning.
>
> Fixes: 6e83985b0f6e ("powerpc/cbe: Do not process external or decremeter interrupts from sreset")
> Reported-by: Naresh Kamboju <redacted>
> Signed-off-by: Anders Roxell <redacted>
> ---
>  arch/powerpc/platforms/cell/pervasive.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/arch/powerpc/platforms/cell/pervasive.c b/arch/powerpc/platforms/cell/pervasive.c
> index 5b9a7e9f144b..dff8d5e7ab82 100644
> --- a/arch/powerpc/platforms/cell/pervasive.c
> +++ b/arch/powerpc/platforms/cell/pervasive.c
> @@ -78,6 +78,7 @@ static int cbe_system_reset_exception(struct pt_regs *regs)
>  	switch (regs->msr & SRR1_WAKEMASK) {
>  	case SRR1_WAKEDEC:
>  		set_dec(1);
> +		break;
>  	case SRR1_WAKEEE:
>  		/*
>  		 * Handle these when interrupts get re-enabled and we take

Thanks. I have definitely fixed this somewhere before, but I guess I
never sent it upstream, or it's still lying in a git stash of mine.

cheers
```