[PATCH 3/7] powerpc/sstep: Fix W=1 compile warning

[Christophe Leroy]

Le 10/09/2020 à 23:02, Cédric Le Goater a écrit :
> ../arch/powerpc/lib/sstep.c: In function ‘mlsd_8lsd_ea’:
> ../arch/powerpc/lib/sstep.c:225:3: error: suggest braces around empty body in an ‘if’ statement [-Werror=empty-body]
>     ; /* Invalid form. Should already be checked for by caller! */
>     ^

A small sentence explaining how this is fixed would be welcome, so that 
you don't need to read the code the know what the commit does to fix the 
warning. Also the subject should be more explicit.



> 
> Cc: Jordan Niethe <jniethe5 at gmail.com>
> Signed-off-by: Cédric Le Goater <clg at kaod.org>
> ---
>   arch/powerpc/lib/sstep.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
> index caee8cc77e19..14572af16e55 100644
> --- a/arch/powerpc/lib/sstep.c
> +++ b/arch/powerpc/lib/sstep.c
> @@ -221,8 +221,9 @@ static nokprobe_inline unsigned long mlsd_8lsd_ea(unsigned int instr,
>   		; /* Leave ea as is */
>   	else if (prefix_r && !ra)
>   		ea += regs->nip;
> -	else if (prefix_r && ra)
> +	else if (prefix_r && ra) {
>   		; /* Invalid form. Should already be checked for by caller! */
> +	}

You can't do that. Now checkpatch will complain that you don't have 
braces on all legs of the if/else dance.

I think the last 'else if' should simply be removed entirely as it does 
nothing. Eventually, just leave the comment, something like:

	/* (prefix_r && ra) is Invalid form. Should already be checked for by 
caller! */

And if (prefix_r && ra) is not possible, then the previous if should 
just be 'if (prefx_r)'

Christophe


>   
>   	return ea;
>   }
>