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Subject[PATCH v2 1/1] arch/sh: avoid spurious sizeof-pointer-div warning
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 by Jakub Jelinek

Signed-off-by: Michael Karcher <>
  - improve title and remove mostly redundant first sentence of the
  - adjust formatting of the _Generic construction

diff --git a/include/linux/sh_intc.h b/include/linux/sh_intc.h
index c255273b0281..98d1da0d8e36 100644
--- a/include/linux/sh_intc.h
+++ b/include/linux/sh_intc.h
@@ -97,7 +97,9 @@ struct intc_hw_desc {
     unsigned int nr_subgroups;

-#define _INTC_ARRAY(a) a, __same_type(a, NULL) ? 0 : sizeof(a)/sizeof(*a)
+#define _INTC_ARRAY(a) a, sizeof(a) / (_Generic(a, \
+                                       typeof(NULL):  (size_t)-1, \
+                                       default:       sizeof(*a)))

 #define INTC_HW_DESC(vectors, groups, mask_regs,    \
              prio_regs,    sense_regs, ack_regs)    \
 \ /
  Last update: 2023-03-26 23:51    [W:0.034 / U:1.036 seconds]
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