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Re: who invented static?

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David Brown <david.brown@hesbynett.no> writes:
> On 07/09/15 19:04, James Kuyper wrote:
[...]
>> The key difference is that without the "static", there's undefined
>> behavior only if the code for func(p) tries to access x[i] for values of
>> i such that p[i] would have undefined behavior. With "static 100", it's
>> also undefined behavior to call the function with a pointer to less than
>> 100 consecutive accessible 'int' objects, regardless of what func()
>> actually does with x.
>
> That's what I thought was the case, but then Tim confused me by saying 
> that without the "static" there is still undefined behaviour if you call 
> the function with a pointer to less than 100 ints, even if the function 
> does not attempt to access them.  If I was merely mistaken in my 
> interpretation of Tim (or if Time made a mistake in his description), 
> then I believe I understand the point.

I don't know whether the mistake was yours or Tim's, but that particular
undefined behavior occurs only when the "static" keyword is present.

[...]

> I agree - that's what would be most useful for me.  That is why I find 
> it particularly disappointing that not only does the standard not 
> specify any diagnostics, it does not even require the code to be 
> consistent in the size of the static array parameters.

A diagnostic cannot be required in all cases, since the size of the
array is not necessarily known at compile time:

    void func(int arr[static 100]);
    int *ptr = malloc(N);
    func(ptr);

In such cases, the standard generally leaves it to individual compilers
to issue warnings when they can.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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who invented static? fir <profesor.fir@gmail.com> - 2015-08-29 11:40 -0700
  Re: who invented static? David Kleinecke <dkleinecke@gmail.com> - 2015-08-29 13:36 -0700
    Re: who invented static? fir <profesor.fir@gmail.com> - 2015-08-29 13:46 -0700
      Re: who invented static? David Kleinecke <dkleinecke@gmail.com> - 2015-08-29 13:53 -0700
        Re: who invented static? James Kuyper <jameskuyper@verizon.net> - 2015-08-29 17:08 -0400
          Re: who invented static? David Brown <david.brown@hesbynett.no> - 2015-08-30 16:56 +0200
            Re: who invented static? James Kuyper <jameskuyper@verizon.net> - 2015-08-30 12:18 -0400
              Re: who invented static? David Brown <david.brown@hesbynett.no> - 2015-08-30 19:00 +0200
                Re: who invented static? Richard Damon <Richard@Damon-Family.org> - 2015-08-30 13:23 -0400
                Re: who invented static? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-08-30 21:18 +0100
                Re: who invented static? Tim Rentsch <txr@alumni.caltech.edu> - 2015-09-06 19:33 -0700
                Re: who invented static? Tim Rentsch <txr@alumni.caltech.edu> - 2015-09-06 19:26 -0700
                Re: who invented static? James Kuyper <jameskuyper@verizon.net> - 2015-08-30 13:40 -0400
                Re: who invented static? supercat@casperkitty.com - 2015-08-31 06:47 -0700
                Re: who invented static? Tim Rentsch <txr@alumni.caltech.edu> - 2015-09-06 19:20 -0700
                Re: who invented static? Tim Rentsch <txr@alumni.caltech.edu> - 2015-09-06 18:59 -0700
                Re: who invented static? David Brown <david.brown@hesbynett.no> - 2015-09-07 10:25 +0200
                Re: who invented static? Keith Thompson <kst-u@mib.org> - 2015-09-07 01:59 -0700
                Re: who invented static? David Brown <david.brown@hesbynett.no> - 2015-09-07 12:22 +0200
                Re: who invented static? James Kuyper <jameskuyper@verizon.net> - 2015-09-07 13:04 -0400
                Re: who invented static? David Brown <david.brown@hesbynett.no> - 2015-09-07 21:25 +0200
                Re: who invented static? James Kuyper <jameskuyper@verizon.net> - 2015-09-07 15:47 -0400
                Re: who invented static? Philip Lantz <prl@canterey.us> - 2015-09-07 13:27 -0700
                Re: who invented static? James Kuyper <jameskuyper@verizon.net> - 2015-09-07 17:31 -0400
                Re: who invented static? David Brown <david.brown@hesbynett.no> - 2015-09-08 09:16 +0200
                Re: who invented static? Keith Thompson <kst-u@mib.org> - 2015-09-07 13:27 -0700
                Re: who invented static? David Brown <david.brown@hesbynett.no> - 2015-09-08 09:12 +0200
                Re: who invented static? Tim Rentsch <txr@alumni.caltech.edu> - 2015-09-07 16:06 -0700
                Re: who invented static? David Brown <david.brown@hesbynett.no> - 2015-09-08 09:08 +0200
                Re: who invented static? Tim Rentsch <txr@alumni.caltech.edu> - 2015-09-12 11:29 -0700
                Re: who invented static? Keith Thompson <kst-u@mib.org> - 2015-09-08 10:18 -0700
                Re: who invented static? James Kuyper <jameskuyper@verizon.net> - 2015-09-08 13:28 -0400
                Re: who invented static? Tim Rentsch <txr@alumni.caltech.edu> - 2015-09-11 10:07 -0700
                Re: who invented static? Tim Rentsch <txr@alumni.caltech.edu> - 2015-09-12 12:30 -0700
                Re: who invented static? David Brown <david.brown@hesbynett.no> - 2015-09-13 15:48 +0200
                Re: who invented static? supercat@casperkitty.com - 2015-09-29 09:04 -0700
                Re: who invented static? Keith Thompson <kst-u@mib.org> - 2015-09-29 09:18 -0700
                Re: who invented static? supercat@casperkitty.com - 2015-09-29 09:57 -0700
        Re: who invented static? fir <profesor.fir@gmail.com> - 2015-08-29 14:18 -0700
          Re: who invented static? fir <profesor.fir@gmail.com> - 2015-09-01 01:36 -0700
    Re: who invented static? Keith Thompson <kst-u@mib.org> - 2015-08-29 14:27 -0700
  Re: who invented static? Siri Cruz <chine.bleu@yahoo.com> - 2015-08-29 14:32 -0700
    Re: who invented static? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-08-29 23:03 +0000
    Re: who invented static? fir <profesor.fir@gmail.com> - 2015-09-01 01:52 -0700
      Re: who invented static? Robert Wessel <robertwessel2@yahoo.com> - 2015-09-01 23:42 -0500
        Re: who invented static? fir <profesor.fir@gmail.com> - 2015-09-02 00:14 -0700
          Re: who invented static? Richard Heathfield <rjh@cpax.org.uk> - 2015-09-02 08:24 +0100
        Re: who invented static? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-09-04 04:25 +0000
          Re: who invented static? fir <profesor.fir@gmail.com> - 2015-09-04 00:45 -0700
            Re: who invented static? Robert Wessel <robertwessel2@yahoo.com> - 2015-09-04 04:09 -0500
              Re: who invented static? fir <profesor.fir@gmail.com> - 2015-09-04 02:35 -0700
                Re: who invented static? Robert Wessel <robertwessel2@yahoo.com> - 2015-09-04 23:58 -0500
                Re: who invented static? fir <profesor.fir@gmail.com> - 2015-09-05 03:02 -0700
                Re: who invented static? wssimms@gmail.com - 2015-09-05 13:14 -0700
                Re: who invented static? fir <profesor.fir@gmail.com> - 2015-09-05 13:49 -0700
                Re: who invented static? Siri Cruz <chine.bleu@yahoo.com> - 2015-09-05 14:09 -0700
                Re: who invented static? gazelle@shell.xmission.com (Kenny McCormack) - 2015-09-05 22:30 +0000
                Re: who invented static? wssimms@gmail.com - 2015-09-05 20:41 -0700
                Re: who invented static? gazelle@shell.xmission.com (Kenny McCormack) - 2015-09-06 05:28 +0000
                Re: who invented static? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-05 22:40 -0700
                Re: who invented static? James Kuyper <jameskuyper@verizon.net> - 2015-09-06 11:42 -0400
                Re: who invented static? Robert Wessel <robertwessel2@yahoo.com> - 2015-09-05 23:38 -0500
                Re: who invented static? raltbos@xs4all.nl (Richard Bos) - 2015-09-27 21:25 +0000
                Re: who invented static? Siri Cruz <chine.bleu@yahoo.com> - 2015-09-27 14:53 -0700
                Re: who invented static? Thomas Richter <thor@math.tu-berlin.de> - 2015-09-29 01:46 +0200
                Re: who invented static? raltbos@xs4all.nl (Richard Bos) - 2015-10-02 12:52 +0000
            Re: who invented static? Siri Cruz <chine.bleu@yahoo.com> - 2015-09-04 02:34 -0700
              Re: who invented static? fir <profesor.fir@gmail.com> - 2015-09-04 02:43 -0700
              Re: who invented static? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-09-05 01:30 +0000
                Re: who invented static? Siri Cruz <chine.bleu@yahoo.com> - 2015-09-04 20:52 -0700
                Re: who invented static? Robert Wessel <robertwessel2@yahoo.com> - 2015-09-05 00:03 -0500
                Re: who invented static? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-09-05 09:04 +0000
                Re: who invented static? fir <profesor.fir@gmail.com> - 2015-09-05 03:02 -0700
                Re: who invented static? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-05 04:33 -0700
                Re: who invented static? Reinhardt Behm <rbehm@hushmail.com> - 2015-09-05 20:08 +0800
                Re: who invented static? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-05 05:21 -0700
                Re: who invented static? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2015-09-05 06:37 -0700
                Re: who invented static? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-09-05 16:54 +0000
                Re: who invented static? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-09-05 11:06 +0100
                Re: who invented static? fir <profesor.fir@gmail.com> - 2015-09-05 03:17 -0700
                Re: who invented static? raltbos@xs4all.nl (Richard Bos) - 2015-09-05 19:14 +0000
                Re: who invented static? fir <profesor.fir@gmail.com> - 2015-09-05 12:59 -0700
            Re: who invented static? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-09-05 01:24 +0000

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