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sh: intc: Avoid spurious sizeof-pointer-div warning

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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
in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108483 by Jakub Jelinek

Signed-off-by: Michael Karcher <kernel@mkarcher.dialup.fu-berlin.de>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Link: https://lore.kernel.org/r/619fa552-c988-35e5-b1d7-fe256c46a272@mkarcher.dialup.fu-berlin.de
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
This commit is contained in:
Michael Karcher 2023-01-24 22:48:16 +01:00 committed by John Paul Adrian Glaubitz
parent c9c3395d5e
commit 250870824c
1 changed files with 4 additions and 1 deletions
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5
include/linux/sh_intc.h
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@ -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) \