Re: [PATCH jiffies] Avoid undefined behavior from signed overflow

[Kevin Easton]

Quoting "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx>:

> On Mon, Jul 29, 2013 at 03:30:35PM +1000, caf@xxxxxxxxxxx wrote:
> > Quoting "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx>:
...
> > >
> > >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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