Re: C programming in 2011

From	James Kuyper <jameskuyper@verizon.net>
Newsgroups	comp.lang.c
Subject	Re: C programming in 2011
Date	2011-05-31 09:23 -0400
Organization	A noiseless patient Spider
Message-ID	<is2q53$qu2$1@dont-email.me> (permalink)
References	(5 earlier) <e2933019-f725-478e-8e4b-b7fa00a17b2d@w21g2000yqm.googlegroups.com> <kfnmxi3p688.fsf@x-alumni2.alumni.caltech.edu> <663f0b2d-4a9a-4a62-bb7c-05202b8b572e@m10g2000yqd.googlegroups.com> <is2gal$suv$1@dont-email.me> <f0682128-aff5-4ac0-a2e2-5bd7ffd3dac0@v10g2000yqn.googlegroups.com>

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On 05/31/2011 08:57 AM, Kleuskes & Moos wrote:
> On May 31, 12:36�pm, James Kuyper <jameskuy...@verizon.net> wrote:
...
>> The closest the standard comes to directly constraining UINT_MAX
>> relative to INT_MAX is in 6.2.5p9: "The range of nonnegative values of a
>> signed integer type is a subrange of the corresponding unsigned integer
>> type, ...". That corresponds to the constraint UINT_MAX >= INT_MAX; it
>> is not violated by UINT_MAX==INT_MAX.
> 
> True. But then there's "not violating a constraint" and there's sheer,
> unadulterated sillyness of actually creating an implementation in
> which UINT_MAX==INT_MAX, since you would be throwing away half the
> range of the unsigned integer (and that goes in all three mandated
> numbersystems).
> 
> So while it may not violate the standard, it _is_ silly, and i would
> very much like to know which compiler meets UINT_MAX==INT_MAX. Just so
> that i can avoid it.

There have been implementations which used the floating point processor
to implement an integer type (probably 'long int'), essentially by using
only mantissa bits, leaving the exponent bits completely unused.
Compared with that, throwing away only half of the potentially
representable range seems pretty minor.

...
>> This does not apply to those unsigned types which are prohibited from
>> having padding bits: unsigned char and the exact-sized types from
>> <stdint.h>, but unsigned int is allowed to have padding bits.
> 
> True. And having these padding bits serves what purpose in your
> opinion? IFAIK the standards guys do nothing without a proper
> rationale.

An obvious possibility is a platform with no hardware support for
unsigned integers - depending upon the precise details of it's
instruction set, it could be easiest to implement unsigned ints as
signed ints with a range restricted to non-negative values. However, I
claim no familiarity with any such system.

I gather that padding bits were allowed because not allowing them would
make creation of a conforming implementation of C more difficult on some
platforms. The wording that describes padding bits was probably more
general than was needed to address the specific platforms the committee
was aware of, but I'm sure they were also concerned about possible
future platforms, and did not desire to unnecessarily constrain the
implementability of C. While they may be obscure platforms, the general
attitude of the C committee seems to be that C should be implementable
almost everywhere, even obscure platforms.
-- 
James Kuyper

Thread

C programming in 2011 Duncan Bayne <dhgbayne@gmail.com> - 2011-05-25 20:27 -0700
  Re: C programming in 2011 Shao Miller <sha0.miller@gmail.com> - 2011-05-25 22:33 -0500
  Re: C programming in 2011 Duncan Bayne <dhgbayne@gmail.com> - 2011-05-25 20:58 -0700
    Re: C programming in 2011 Duncan Bayne <dhgbayne@gmail.com> - 2011-05-25 21:06 -0700
      Re: C programming in 2011 Shao Miller <sha0.miller@gmail.com> - 2011-05-25 23:24 -0500
  Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-05-26 07:51 +0000
    Re: C programming in 2011 Chris H <chris@phaedsys.org> - 2011-05-26 11:15 +0100
      Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-05-26 06:53 -0400
        Re: C programming in 2011 Ian Collins <ian-news@hotmail.com> - 2011-05-27 09:12 +1200
      Re: C programming in 2011 Nizumzen <chicken@mcnuggets.com> - 2011-05-29 00:39 +0100
        Re: C programming in 2011 Noob <root@127.0.0.1> - 2011-06-01 17:38 +0200
          Re: C programming in 2011 Nizumzen <chicken@mcnuggets.com> - 2011-06-01 22:34 +0100
            Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-06-01 21:42 +0000
              Re: C programming in 2011 Nizumzen <chicken@mcnuggets.com> - 2011-06-02 00:33 +0100
    Re: C programming in 2011 Duncan Bayne <dhgbayne@gmail.com> - 2011-05-26 03:41 -0700
      Re: C programming in 2011 Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-05-28 00:46 +0000
    Re: C programming in 2011 Chad <cdalten@gmail.com> - 2011-05-26 14:09 -0700
      Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-05-26 15:07 -0700
      Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-05-27 07:42 +0000
      Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-05-27 07:30 -0400
    Re: C programming in 2011 Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-05-29 01:15 +0300
      Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-05-28 22:24 +0000
        Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-05-28 16:08 -0700
          Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-05-28 23:47 +0000
            Re: C programming in 2011 Geoff <geoff@invalid.invalid> - 2011-05-28 16:58 -0700
              Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-05-28 18:49 -0700
                Re: C programming in 2011 Pierre Habouzit <madcoder@debian.org> - 2011-05-29 11:13 +0000
                Re: C programming in 2011 Jorge <jorge@jorgechamorro.com> - 2011-06-04 08:05 -0700
                Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-06-04 16:20 +0000
                Re: C programming in 2011 Nizumzen <chicken@mcnuggets.com> - 2011-05-29 14:35 +0100
                Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-05-29 12:49 -0700
                OT: Brackets, parentheses, etc. (Was: C programming in 2011) Shao Miller <sha0.miller@gmail.com> - 2011-05-29 16:13 -0500
                Re: OT: Brackets, parentheses, etc. (Was: C programming in 2011) "Morris Keesan" <mkeesan@post.harvard.edu> - 2011-05-30 12:17 -0400
                Re: OT: Brackets, parentheses, etc. (Was: C programming in 2011) Shao Miller <sha0.miller@gmail.com> - 2011-05-30 12:52 -0500
                Re: C programming in 2011 Nizumzen <chicken@mcnuggets.com> - 2011-05-29 23:58 +0100
                Re: C programming in 2011 Chris H <chris@phaedsys.org> - 2011-05-30 14:42 +0100
                Re: C programming in 2011 Nizumzen <chicken@mcnuggets.com> - 2011-05-30 17:40 +0100
                Re: C programming in 2011 Sjouke Burry <burrynulnulfour@ppllaanneett.nnll> - 2011-05-30 22:38 +0200
                Re: C programming in 2011 "J. J. Farrell" <jjf@bcs.org.uk> - 2011-05-30 00:38 +0100
                Re: C programming in 2011 Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-05-30 11:14 +0300
              Re: C programming in 2011 Malcolm McLean <malcolm.mclean5@btinternet.com> - 2011-05-29 06:55 -0700
            Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-05-28 18:47 -0700
              Re: C programming in 2011 Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-05-30 15:02 +0300
        Re: C programming in 2011 Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-05-30 11:01 +0300
          Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-05-30 08:51 +0000
            Re: C programming in 2011 Nobody <nobody@nowhere.com> - 2011-05-31 01:54 +0100
              Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-05-31 12:00 +0000
                Re: C programming in 2011 Seebs <usenet-nospam@seebs.net> - 2011-05-31 16:44 +0000
                Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-05-31 11:43 -0700
  Re: C programming in 2011 Chris H <chris@phaedsys.org> - 2011-05-26 11:13 +0100
  Re: C programming in 2011 Francois Grieu <fgrieu@gmail.com> - 2011-05-26 16:04 +0200
    Re: C programming in 2011 Branimir Maksimovic <bmaxa@hotmail.com> - 2011-05-26 16:21 +0200
      Re: C programming in 2011 Francois Grieu <fgrieu@gmail.com> - 2011-05-26 17:23 +0200
        Re: C programming in 2011 Branimir Maksimovic <bmaxa@hotmail.com> - 2011-05-26 19:15 +0200
          Re: C programming in 2011 Willem <willem@toad.stack.nl> - 2011-05-26 17:29 +0000
            Re: C programming in 2011 Branimir Maksimovic <bmaxa@hotmail.com> - 2011-05-26 20:10 +0200
          Re: C programming in 2011 Pierre Habouzit <madcoder@debian.org> - 2011-05-26 17:35 +0000
            Re: C programming in 2011 Willem <willem@toad.stack.nl> - 2011-05-26 17:53 +0000
              Re: C programming in 2011 Malcolm McLean <malcolm.mclean5@btinternet.com> - 2011-05-26 11:13 -0700
                Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-05-26 21:57 -0400
                Re: C programming in 2011 Tim Rentsch <txr@alumni.caltech.edu> - 2011-05-31 01:13 -0700
            Re: C programming in 2011 Branimir Maksimovic <bmaxa@hotmail.com> - 2011-05-26 20:06 +0200
          Re: C programming in 2011 Ralf Damaschke <rwspam@gmx.de> - 2011-05-26 17:57 +0000
            Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-05-26 11:31 -0700
              Re: C programming in 2011 Ralf Damaschke <rwspam@gmx.de> - 2011-05-26 20:43 +0000
                Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-05-26 14:53 -0700
        Re: C programming in 2011 Tim Rentsch <txr@alumni.caltech.edu> - 2011-05-31 01:03 -0700
          Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-05-31 01:59 -0700
            Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-05-31 02:55 -0700
              Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-05-31 06:36 -0400
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-05-31 05:57 -0700
                Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-05-31 09:23 -0400
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-05-31 07:50 -0700
                Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-05-31 11:41 -0700
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-01 01:46 -0700
                Re: C programming in 2011 Ike Naar <ike@iceland.freeshell.org> - 2011-06-01 10:07 +0000
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-01 04:12 -0700
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-01 07:46 -0700
                Re: C programming in 2011 Seebs <usenet-nospam@seebs.net> - 2011-06-01 17:53 +0000
                Re: C programming in 2011 lawrence.jones@siemens.com - 2011-06-01 16:28 -0400
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-01 23:28 -0700
                Re: C programming in 2011 Uno <Uno@example.invalid> - 2011-06-09 21:24 -0600
                Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-06-01 10:04 -0400
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-01 08:21 -0700
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-01 09:37 -0700
                Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-06-01 12:55 -0400
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-01 11:52 -0700
                Re: C programming in 2011 "J. J. Farrell" <jjf@bcs.org.uk> - 2011-06-02 00:00 +0100
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-01 23:19 -0700
                Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-06-01 12:53 -0400
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-01 11:55 -0700
                Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-06-01 08:41 -0700
                Re: C programming in 2011 Noob <root@127.0.0.1> - 2011-06-01 17:12 +0200
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-01 09:28 -0700
                Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-06-01 08:38 -0700
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-02 01:00 -0700
                Re: C programming in 2011 Willem <willem@toad.stack.nl> - 2011-06-02 09:13 +0000
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-02 02:52 -0700
                Re: C programming in 2011 Willem <willem@toad.stack.nl> - 2011-06-02 11:41 +0000
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-02 05:53 -0700
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-02 06:49 -0700
                Re: C programming in 2011 Willem <willem@toad.stack.nl> - 2011-06-02 14:18 +0000
                Re: C programming in 2011 Seebs <usenet-nospam@seebs.net> - 2011-06-02 21:02 +0000
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-02 23:55 -0700
                Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-06-03 08:37 +0000
                Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-06-03 06:49 -0400
                Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-06-03 11:52 +0000
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-03 11:11 -0700
                Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-06-03 18:23 +0000
                Re: C programming in 2011 Seebs <usenet-nospam@seebs.net> - 2011-06-03 18:59 +0000
                Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-06-03 19:48 +0000
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-03 15:02 -0700
                Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-06-03 12:19 -0700
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-03 13:40 -0700
                Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-06-03 15:11 -0700
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-03 15:24 -0700
                Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-06-03 15:34 -0700
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-03 17:10 -0700
                Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-06-03 17:34 -0700
                Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-06-04 09:47 -0400
                Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-06-02 10:02 -0400
                Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-06-02 12:17 +0000
                Re: C programming in 2011 Keith Thompson <kst-u@mib.org> - 2011-06-02 08:48 -0700
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-02 10:35 -0700
                Re: C programming in 2011 gordonb.jpem8@burditt.org (Gordon Burditt) - 2011-06-05 23:32 -0500
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-06 00:12 -0700
                Re: C programming in 2011 gordonb.5k8u2@burditt.org (Gordon Burditt) - 2011-06-06 05:18 -0500
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-06 08:16 -0700
                Re: C programming in 2011 Michael Press <rubrum@pacbell.net> - 2011-06-03 18:06 -0700
                Re: C programming in 2011 gordonb.zourz@burditt.org (Gordon Burditt) - 2011-06-05 21:25 -0500
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-06 01:14 -0700
                Re: C programming in 2011 gordonb.donaz@burditt.org (Gordon Burditt) - 2011-06-06 04:36 -0500
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-06 09:02 -0700
                Re: C programming in 2011 gordonb.k6ruq@burditt.org (Gordon Burditt) - 2011-06-06 18:36 -0500
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-07 10:14 -0700
                Re: C programming in 2011 "J. J. Farrell" <jjf@bcs.org.uk> - 2011-05-31 19:56 +0100
                Re: C programming in 2011 Noob <root@127.0.0.1> - 2011-06-01 14:54 +0200
                Re: C programming in 2011 Angel <angel+news@spamcop.net> - 2011-06-01 13:07 +0000
                Re: C programming in 2011 pete <pfiland@mindspring.com> - 2011-06-01 14:10 -0400
                Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-06-01 19:58 -0400
                Re: C programming in 2011 Willem <willem@toad.stack.nl> - 2011-06-01 09:07 +0000
                Re: C programming in 2011 James Kuyper <jameskuyper@verizon.net> - 2011-06-01 09:29 -0400
                Re: C programming in 2011 David Thompson <dave.thompson2@verizon.net> - 2011-06-07 02:18 -0400
                Re: C programming in 2011 "Kleuskes & Moos" <kleuske@xs4all.nl> - 2011-06-07 09:31 -0700
                Re: C programming in 2011 Patrick Scheible <kkt@zipcon.net> - 2011-06-09 14:55 -0700
              Re: C programming in 2011 Tim Rentsch <txr@alumni.caltech.edu> - 2011-06-01 02:35 -0700
          Re: C programming in 2011 Francois Grieu <fgrieu@gmail.com> - 2011-05-31 21:57 +0200
            Re: C programming in 2011 Francois Grieu <fgrieu@gmail.com> - 2011-05-31 22:03 +0200
  Re: C programming in 2011 Kenneth Brody <kenbrody@spamcop.net> - 2011-05-26 12:27 -0400
  Re: C programming in 2011 Nobody <nobody@nowhere.com> - 2011-05-26 18:02 +0100

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