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SubjectRe: [PATCH jiffies] Avoid undefined behavior from signed overflow
Quoting "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>:

> On Mon, Jul 29, 2013 at 03:30:35PM +1000, caf@guarana.org wrote:
>> Quoting "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>:
>>
...
>> >
>> >Note that the C standard considers the cast from signed to
>> >unsigned to be implementation-defined, see 6.3.1.3p3.
...
>>
>> Don't worry, the case from signed to unsigned is actually well-defined -
>> the relevant part is 6.3.1.3p2 (in C99):
>>
>> >Otherwise, if the new type is unsigned, the value is converted by
>> >repeatedly adding or subtracting one more than the maximum value that
>> >can be represented in the new type until the value is in the range of
>> >the new type.
>
> Yep, but we are going in the other direction, from unsigned to signed.

Ahh, there's an error in the commit message (it says signed to unsigned).

- Kevin

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