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Re: Is this defined behavior?

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Malcolm McLean <malcolm.arthur.mclean@gmail.com> writes:
> On 03/02/2024 08:44, Tim Rentsch wrote:
>> Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:
>>> Anthony Cuozzo <anthony@cuozzo.us> writes:
>>>> Time T:  Add N to a uintptr_t
>>>>
>>>> Time T+1:  Subtract N from that same uintptr_t
>>>>
>>>> Questions:
>>>>
>>>> 1.  Is this behavior defined?
>>>
>>> Sure, why wouldn't it be?  uintptr_t is just an unsigned integer
>>> type.  The guarantees about converting to and from void* don't
>>> affect its arithmetic behavior.  Adding and then subtracting N
>>> yields the original value.
>> Extremely likely to hold.  A perverse implementation could choose
>> (IIANM) a uintptr_t whose integer conversion rank is less than
>> that of int, and that could mess things up.  In practical terms
>> though what you say is spot on.
>
> OK, so this is completely topical and there's no issue there. But it's
> also fair to say that it's the sort of post which gives the newgroup a 
> bad reputation.
>
> I'm not going to take a position. But since we've had complaints about
> the diection things are going in, other people might like to weigh in
> on this.

What on Earth are you talking about?

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for Medtronic
void Void(void) { Void(); } /* The recursive call of the void */

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Thread

Is this defined behavior? Anthony Cuozzo <anthony@cuozzo.us> - 2024-02-02 10:56 -0500
  Re: Is this defined behavior? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-02-02 08:28 -0800
    Re: Is this defined behavior? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-02-03 00:44 -0800
      Re: Is this defined behavior? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2024-02-03 16:07 +0000
        Re: Is this defined behavior? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-02-03 13:41 -0800
          Re: Is this defined behavior? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2024-02-04 03:18 +0000
            Re: Is this defined behavior? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-02-03 19:48 -0800
              Re: Is this defined behavior? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2024-02-04 04:34 +0000
        Re: Is this defined behavior? David Brown <david.brown@hesbynett.no> - 2024-02-04 13:24 +0100
          Re: Is this defined behavior? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2024-02-04 15:16 +0000
            Re: Is this defined behavior? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-02-04 13:31 -0800
              Re: Is this defined behavior? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2024-02-04 23:18 +0000
                Re: Is this defined behavior? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-02-04 15:56 -0800
                Re: Is this defined behavior? gazelle@shell.xmission.com (Kenny McCormack) - 2024-02-05 00:05 +0000
                Re: Is this defined behavior? Poprocks <please@replytogroup.com> - 2024-02-05 13:35 -0500
                Re: Is this defined behavior? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2024-02-06 13:10 +0000
                Is this sane behavior? (Was: Is this defined behavior?) gazelle@shell.xmission.com (Kenny McCormack) - 2024-02-06 14:52 +0000
                Re: Is this sane behavior? (Was: Is this defined behavior?) Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2024-02-06 15:50 +0000
              Re: Is this defined behavior? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-02-04 23:21 -0800
          Re: Is this defined behavior? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2024-02-04 15:27 +0000
            Re: Is this defined behavior? David Brown <david.brown@hesbynett.no> - 2024-02-04 18:23 +0100

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