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SubjectRe: [PATCH 1/6] rtc: generic: allow building on all architectures
Date
Geert Uytterhoeven <geert@linux-m68k.org> writes:

>> +#else
>> +#define generic_rtc_ops *(struct rtc_class_ops*)NULL
>> +#endif
>>
>> static int __init generic_rtc_probe(struct platform_device *dev)
>> {
>> struct rtc_device *rtc;
>> + const struct rtc_class_ops *ops;
>> +
>> + ops = dev_get_platdata(&dev->dev);
>> + if (!ops)
>> + ops = &generic_rtc_ops;
>
> I hope no compiler version treats "&*(struct rtc_class_ops*)NULL" as
> undefined behavior?

Yes, that is guaranteed, the operations cancel each other (6.5.3.2#3: If
the operand is the result of a unary * operator, neither that operator
nor the & operator is evaluated and the result is as if both were
omitted).

Andreas.

--
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5
"And now for something completely different."

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