Re: Is this code considered to transgress the signed overflow purism?

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From	Keith Thompson <kst-u@mib.org>
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Subject	Re: Is this code considered to transgress the signed overflow purism?
Date	Sun, 30 Apr 2017 12:41:35 -0700
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Tim Rentsch <txr@alumni.caltech.edu> writes:
[...]
> For use in pre-processor conditionals, generally <limits.h> is
> needed, because (a) sizeof doesn't work in #if etc, and (b)
> even if it did, the sizes of types are potentially different in
> the pre-processor than they are in the program.

I'm not sure how meaningful your point (b) is.  *If* the preprocessor
were modified to permit sizeof, then it would be reasonable to
require that for example sizeof (long) must reflect the size of
type long on the target system.  In fact, I'd say it would be
unreasonable not to require that.  (In reality, the preprocessor
treats integer expressions as if they were of type intmax_t or
uintmax_t.  N1570 6.10.1p4.)

That reminds me of a discussion on comp.std.c back in 1998.  The
relevant quotation:

| > You are right.  It was nice back in the days when things like
| > 
| > #if (sizeof(int) == 8)
| > 
| > actually worked (on some compilers).
| 
| Must have been before my time.
| 
|      Dennis

Yes, the poster was Dennis Ritchie.

-- 
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"

Thread

Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-04-27 03:13 -0700
  Re: Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-04-27 03:41 -0700
  Re: Is this code considered to transgress the signed overflow purism? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-27 11:59 +0100
    Re: Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-04-27 14:35 -0700
      Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-04-27 15:13 -0700
        Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-28 00:58 +0200
          Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-04-27 16:44 -0700
            Re: Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-04-27 20:04 -0700
            Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-28 08:53 +0200
              Re: Is this code considered to transgress the signed overflow purism? supercat@casperkitty.com - 2017-04-28 08:23 -0700
                Re: Is this code considered to transgress the signed overflow purism? Manfred <noname@invalid.add> - 2017-04-28 18:05 +0200
                Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-04-28 09:22 -0700
                Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-04-28 12:24 -0700
                Re: Is this code considered to transgress the signed overflow purism? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-29 00:03 +0100
                Re: Is this code considered to transgress the signed overflow purism? supercat@casperkitty.com - 2017-04-28 16:37 -0700
                Re: Is this code considered to transgress the signed overflow purism? David Kleinecke <dkleinecke@gmail.com> - 2017-04-28 17:09 -0700
                Re: Is this code considered to transgress the signed overflow purism? supercat@casperkitty.com - 2017-04-28 17:34 -0700
                Re: Is this code considered to transgress the signed overflow purism? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-29 01:43 +0100
                Re: Is this code considered to transgress the signed overflow purism? David Kleinecke <dkleinecke@gmail.com> - 2017-04-28 21:21 -0700
                Re: Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-04-29 02:04 -0700
                Re: Is this code considered to transgress the signed overflow purism? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-29 11:46 +0100
                Re: Is this code considered to transgress the signed overflow purism? Robert Wessel <robertwessel2@yahoo.com> - 2017-04-30 12:05 -0500
                Re: Is this code considered to transgress the signed overflow purism? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-29 11:33 +0100
                Re: Is this code considered to transgress the signed overflow purism? David Kleinecke <dkleinecke@gmail.com> - 2017-04-29 08:26 -0700
                Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-29 17:58 +0200
                Re: Is this code considered to transgress the signed overflow purism? David Kleinecke <dkleinecke@gmail.com> - 2017-04-29 09:13 -0700
                Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-30 12:55 +0200
                Re: Is this code considered to transgress the signed overflow purism? David Kleinecke <dkleinecke@gmail.com> - 2017-04-30 09:17 -0700
                Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-30 20:35 +0200
                Re: Is this code considered to transgress the signed overflow purism? David Kleinecke <dkleinecke@gmail.com> - 2017-04-30 15:39 -0700
                Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-05-01 16:21 +0200
                Re: Is this code considered to transgress the signed overflow purism? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2017-05-02 06:35 -0700
                Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-05-02 16:29 +0200
                Re: Is this code considered to transgress the signed overflow purism? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-29 20:58 +0100
                Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-28 18:43 +0200
            Re: Is this code considered to transgress the signed overflow purism? bartc <bc@freeuk.com> - 2017-04-28 14:09 +0100
              Re: Is this code considered to transgress the signed overflow purism? scott@slp53.sl.home (Scott Lurndal) - 2017-04-28 14:23 +0000
                Re: Is this code considered to transgress the signed overflow purism? bartc <bc@freeuk.com> - 2017-04-28 16:17 +0100
                Re: Is this code considered to transgress the signed overflow purism? scott@slp53.sl.home (Scott Lurndal) - 2017-04-28 15:55 +0000
                Re: Is this code considered to transgress the signed overflow purism? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2017-04-28 19:11 -0700
                Re: Is this code considered to transgress the signed overflow purism? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-29 11:23 +0100
                Re: Is this code considered to transgress the signed overflow purism? bartc <bc@freeuk.com> - 2017-04-29 11:31 +0100
                Re: Is this code considered to transgress the signed overflow purism? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-29 12:01 +0100
                Re: Is this code considered to transgress the signed overflow purism? bartc <bc@freeuk.com> - 2017-04-29 12:47 +0100
                Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-29 15:20 +0200
                Re: Is this code considered to transgress the signed overflow purism? bartc <bc@freeuk.com> - 2017-04-29 15:22 +0100
                Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-29 16:52 +0200
                Re: Is this code considered to transgress the signed overflow purism? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-29 15:18 +0100
                Re: Is this code considered to transgress the signed overflow purism? Jean-Marc Bourguet <jm@bourguet.org> - 2017-04-29 14:25 +0200
                Re: Is this code considered to transgress the signed overflow purism? Jerry Stuckle <jstucklex@attglobal.net> - 2017-04-29 08:05 -0400
                Re: Is this code considered to transgress the signed overflow purism? Gareth Owen <gwowen@gmail.com> - 2017-04-29 13:34 +0100
                Re: Is this code considered to transgress the signed overflow purism? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2017-04-29 05:55 -0700
                Re: Is this code considered to transgress the signed overflow purism? GOTHIER Nathan <nathan.gothier@gmail.com> - 2017-04-29 15:11 +0200
                Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-29 15:24 +0200
                Re: Is this code considered to transgress the signed overflow purism? Gareth Owen <gwowen@gmail.com> - 2017-04-29 14:57 +0100
                Re: Is this code considered to transgress the signed overflow purism? asetofsymbols@gmail.com - 2017-05-03 12:17 -0700
                Re: Is this code considered to transgress the signed overflow purism? supercat@casperkitty.com - 2017-05-03 16:36 -0700
                Re: Is this code considered to transgress the signed overflow purism? asetofsymbols@gmail.com - 2017-05-03 11:26 -0700
                Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-05-03 21:40 +0200
                Re: Is this code considered to transgress the signed overflow purism? asetofsymbols@gmail.com - 2017-05-03 23:46 -0700
              Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-04-28 08:55 -0700
        Re: Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-04-27 20:20 -0700
          Re: Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-04-27 20:26 -0700
          Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-28 10:19 +0200
            Re: Is this code considered to transgress the signed overflow purism? James Kuyper <jameskuyper@verizon.net> - 2017-04-28 09:57 -0400
              Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-28 17:06 +0200
            Re: Is this code considered to transgress the signed overflow purism? supercat@casperkitty.com - 2017-04-28 08:38 -0700
              Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-28 18:51 +0200
            Re: Is this code considered to transgress the signed overflow purism? supercat@casperkitty.com - 2017-04-29 12:43 -0700
              Re: Is this code considered to transgress the signed overflow purism? Tim Rentsch <txr@alumni.caltech.edu> - 2017-04-30 14:02 -0700
                Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-04-30 14:25 -0700
                Re: Is this code considered to transgress the signed overflow purism? Tim Rentsch <txr@alumni.caltech.edu> - 2017-04-30 15:01 -0700
          Re: Is this code considered to transgress the signed overflow purism? James Kuyper <jameskuyper@verizon.net> - 2017-04-28 09:48 -0400
          Re: Is this code considered to transgress the signed overflow purism? supercat@casperkitty.com - 2017-04-28 08:07 -0700
            Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-28 18:56 +0200
              Re: Is this code considered to transgress the signed overflow purism? supercat@casperkitty.com - 2017-04-28 11:30 -0700
          Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-04-28 08:35 -0700
      Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-28 00:54 +0200
        Re: Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-04-27 21:05 -0700
          Re: Is this code considered to transgress the signed overflow purism? David Brown <david.brown@hesbynett.no> - 2017-04-28 10:58 +0200
            Re: Is this code considered to transgress the signed overflow purism? bartc <bc@freeuk.com> - 2017-04-28 10:50 +0100
          Re: Is this code considered to transgress the signed overflow purism? James Kuyper <jameskuyper@verizon.net> - 2017-04-28 10:01 -0400
            Re: Is this code considered to transgress the signed overflow purism? Tim Rentsch <txr@alumni.caltech.edu> - 2017-05-02 05:06 -0700
      Re: Is this code considered to transgress the signed overflow purism? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-28 23:57 +0100
      Re: Is this code considered to transgress the signed overflow purism? Tim Rentsch <txr@alumni.caltech.edu> - 2017-04-30 12:28 -0700
        Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-04-30 12:41 -0700
          Re: Is this code considered to transgress the signed overflow purism? bartc <bc@freeuk.com> - 2017-04-30 21:46 +0100
            Re: Is this code considered to transgress the signed overflow purism? Thiago Adams <thiago.adams@gmail.com> - 2017-05-01 05:41 -0700
              Re: Is this code considered to transgress the signed overflow purism? bartc <bc@freeuk.com> - 2017-05-01 13:57 +0100
            Re: Is this code considered to transgress the signed overflow purism? Tim Rentsch <txr@alumni.caltech.edu> - 2017-05-02 05:30 -0700
              Re: Is this code considered to transgress the signed overflow purism? bartc <bc@freeuk.com> - 2017-05-02 16:13 +0100
                Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-05-02 09:12 -0700
                Re: Is this code considered to transgress the signed overflow purism? bartc <bc@freeuk.com> - 2017-05-02 18:15 +0100
                Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-05-02 11:26 -0700
                Re: Is this code considered to transgress the signed overflow purism? bartc <bc@freeuk.com> - 2017-05-02 21:39 +0100
                Re: Is this code considered to transgress the signed overflow purism? supercat@casperkitty.com - 2017-05-02 13:53 -0700
                Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-05-02 14:10 -0700
                Re: Is this code considered to transgress the signed overflow purism? bartc <bc@freeuk.com> - 2017-05-02 22:36 +0100
                Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-05-02 15:27 -0700
                Re: Is this code considered to transgress the signed overflow purism? Robert Wessel <robertwessel2@yahoo.com> - 2017-05-03 00:45 -0500
                Re: Is this code considered to transgress the signed overflow purism? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-05-03 11:57 +0100
                Re: Is this code considered to transgress the signed overflow purism? Robert Wessel <robertwessel2@yahoo.com> - 2017-05-03 13:34 -0500
                Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-05-03 12:05 -0700
                Re: Is this code considered to transgress the signed overflow purism? Tim Rentsch <txr@alumni.caltech.edu> - 2017-05-05 02:58 -0700
                Re: Is this code considered to transgress the signed overflow purism? Thiago Adams <thiago.adams@gmail.com> - 2017-05-03 05:26 -0700
                Re: Is this code considered to transgress the signed overflow purism? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2017-05-03 05:54 -0700
                Re: Is this code considered to transgress the signed overflow purism? Thiago Adams <thiago.adams@gmail.com> - 2017-05-03 06:49 -0700
                Re: Is this code considered to transgress the signed overflow purism? Thiago Adams <thiago.adams@gmail.com> - 2017-05-03 06:51 -0700
                Re: Is this code considered to transgress the signed overflow purism? jadill33@gmail.com - 2017-05-03 09:03 -0700
                Re: Is this code considered to transgress the signed overflow purism? supercat@casperkitty.com - 2017-05-02 14:47 -0700
                Re: Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-05-03 17:45 -0700
          Re: Is this code considered to transgress the signed overflow purism? Tim Rentsch <txr@alumni.caltech.edu> - 2017-04-30 14:42 -0700
        Re: Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-04-30 23:57 -0700
          Re: Is this code considered to transgress the signed overflow purism? Tim Rentsch <txr@alumni.caltech.edu> - 2017-05-02 04:32 -0700
            Re: Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-05-03 18:20 -0700
          Re: Is this code considered to transgress the signed overflow purism? luser droog <luser.droog@gmail.com> - 2017-05-08 23:12 -0700
            Re: Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-05-09 19:54 -0700
              Re: Is this code considered to transgress the signed overflow purism? luser droog <luser.droog@gmail.com> - 2017-05-09 21:21 -0700
  Re: Is this code considered to transgress the signed overflow purism? James Kuyper <jameskuyper@verizon.net> - 2017-04-27 10:46 -0400
    Re: Is this code considered to transgress the signed overflow purism? supercat@casperkitty.com - 2017-04-27 08:37 -0700
      Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-04-27 09:38 -0700
        Re: Is this code considered to transgress the signed overflow purism? supercat@casperkitty.com - 2017-04-27 10:17 -0700
          Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-04-27 12:10 -0700
        Re: Is this code considered to transgress the signed overflow purism? Tim Rentsch <txr@alumni.caltech.edu> - 2017-04-30 13:50 -0700
          Re: Is this code considered to transgress the signed overflow purism? Keith Thompson <kst-u@mib.org> - 2017-04-30 14:11 -0700
            Re: Is this code considered to transgress the signed overflow purism? Tim Rentsch <txr@alumni.caltech.edu> - 2017-04-30 14:44 -0700
            Re: Is this code considered to transgress the signed overflow purism? joel.rees@gmail.com - 2017-04-30 22:05 -0700

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