Re: [PATCH 01/21] powerpc: Remove warning on array size when empty

[Mathieu Malaterre]

On Thu, Mar 1, 2018 at 3:55 AM, Michael Ellerman <mpe@xxxxxxxxxxxxxx> wrote:
> Mathieu Malaterre <malat@xxxxxxxxxx> writes:
>
>> When neither CONFIG_ALTIVEC, nor CONFIG_VSX or CONFIG_PPC64 is defined, the
>> array feature_properties is defined as an empty array, which in turn
>> triggers the following warning (treated as error on W=1):
>>
>>   CC      arch/powerpc/kernel/prom.o
>> arch/powerpc/kernel/prom.c: In function âcheck_cpu_feature_propertiesâ:
>> arch/powerpc/kernel/prom.c:298:16: error: comparison of unsigned expression < 0 is always false [-Werror=type-limits]
>>   for (i = 0; i < ARRAY_SIZE(feature_properties); ++i, ++fp) {
>>                 ^
>> cc1: all warnings being treated as errors
>
> Ugh, that's annoying.
>
> This seems to work?
>
> diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
> index 4dffef947b8a..5215119e249c 100644
> --- a/arch/powerpc/kernel/prom.c
> +++ b/arch/powerpc/kernel/prom.c
> @@ -291,11 +291,11 @@ static inline void identical_pvr_fixup(unsigned long node)
>
>  static void __init check_cpu_feature_properties(unsigned long node)
>  {
> -       unsigned long i;
>         struct feature_property *fp = feature_properties;
>         const __be32 *prop;
> +       int i;
>
> -       for (i = 0; i < ARRAY_SIZE(feature_properties); ++i, ++fp) {
> +       for (i = 0; i < (int)ARRAY_SIZE(feature_properties); ++i, ++fp) {
>                 prop = of_get_flat_dt_prop(node, fp->name, NULL);
>                 if (prop && be32_to_cpup(prop) >= fp->min_value) {
>                         cur_cpu_spec->cpu_features |= fp->cpu_feature;
>

Indeed that looks like the less invasive solution, I'll re-submit.

Should I resubmit the entire patch series (21 indep patches) or
re-submit only the 3 patches that were discussed (as part of a
different series) ?

Thanks