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    SubjectRe: [PATCH v5 1/1] arch/sh: avoid spurious sizeof-pointer-div warning
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    Hello!

    On 1/23/23 21:05, Michael Karcher wrote:
    > Gcc warns about the pattern sizeof(void*)/sizeof(void), as it looks like
    > the abuse of a pattern to calculate the array size. This pattern appears
    > in the unevaluated part of the ternary operator in _INTC_ARRAY if the
    > parameter is NULL.
    >
    > The replacement uses an alternate approach to return 0 in case of NULL
    > which does not generate the pattern sizeof(void*)/sizeof(void), but still
    > emits the warning if _INTC_ARRAY is called with a nonarray parameter.
    >
    > This patch is required for successful compilation with -Werror enabled.
    >
    > The idea to use _Generic for type distinction is taken from Comment #7
    > inhttps://gcc.gnu.org/bugzilla/show_bug.cgi?id=108483 by Jakub Jelinek
    >
    > Signed-off-by: Michael Karcher<kernel@mkarcher.dialup.fu-berlin.de>
    > ---
    > History:
    > v5:
    > - Cleanly generated the patch
    > v4:
    > - Put the case distinction into the numerator instead of the denominator
    > - Refactor the case disctinction into a second macro
    > v3:
    > - I had a stern discussion with Thunderbird about not mangling the
    > space characters in my email, and I hope spaces get sent as standard
    > spaces now
    > v2:
    > - improve title and remove mostly redundant first sentence of the
    > description
    > - adjust formatting of the _Generic construction
    >
    > diff --git a/include/linux/sh_intc.h b/include/linux/sh_intc.h
    > index c255273b0281..37ad81058d6a 100644
    > --- a/include/linux/sh_intc.h
    > +++ b/include/linux/sh_intc.h
    > @@ -97,7 +97,10 @@ struct intc_hw_desc {
    > unsigned int nr_subgroups;
    > };
    >
    > -#define _INTC_ARRAY(a) a, __same_type(a, NULL) ? 0 : sizeof(a)/sizeof(*a)
    > +#define _INTC_SIZEOF_OR_ZERO(a) (_Generic(a, \
    > + typeof(NULL): 0, \
    > + default: sizeof(a)))
    > +#define _INTC_ARRAY(a) a, _INTC_SIZEOF_OR_ZERO(a)/sizeof(*a)
    >
    > #define INTC_HW_DESC(vectors, groups, mask_regs, \
    > prio_regs, sense_regs, ack_regs) \

    Can anyone suggest which tree to pick this up through until we have established a
    new linux-sh tree?

    Shall this go through Andrew's tree?

    Adrian

    --
    .''`. John Paul Adrian Glaubitz
    : :' : Debian Developer
    `. `' Physicist
    `- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913

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