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Re: OT: One of Anton's papers makes Hacker News

From Keith Thompson <kst-u@mib.org>
Newsgroups comp.lang.c, comp.lang.forth
Subject Re: OT: One of Anton's papers makes Hacker News
Date 2016-03-15 08:56 -0700
Organization None to speak of
Message-ID <ln60wnivkq.fsf@kst-u.example.com> (permalink)
References (15 earlier) <nc7esp$tsi$1@dont-email.me> <lny49kiqyc.fsf@kst-u.example.com> <nc7m5h$ckk$1@dont-email.me> <lnmvq0i9yw.fsf@kst-u.example.com> <56e7df44$0$24111$e4fe514c@news.xs4all.nl>

Cross-posted to 2 groups.

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Albert van der Horst <albert@spenarnc.xs4all.nl> writes:
> Keith Thompson <kst-u@mib.org> writes:
>
> <SNIP>
>>I think I have a pretty good idea what people who use the phrase
>>"portable assembler" are trying to express.  I just happen to think that
>>it's an incorrect use of the word "assembler".  Calling C an "assembler"
>>makes the word "assembler" less useful, because it no longer expresses a
>>particularly useful concept.
>
> We in Holland we talk about can (blik which means tin plated steal)
> that is made of ... plastic. Original battery (at least in Europe) means
> several electric cells tied together. Now it is often used
> for a monocell, which is in fact incorrect, but not after 100+ years.
> "portable assembler" is metaphorical and after a while the expression
> takes on a meaning of its own.
> You understand what it means, that is good enough for me.
> Let me use scare quotes in order to not annoy you.
>
> Original C was usable and used as a "portable assembler".
>
> Do you agree that the concept that "portable assembler" tries
> to describe, is important, and helps to convey insight?

Tries to describe?  Sure.

Is important?  Meh.

Helps to convey insight?  No.

> Gcc is used to implement other languages.
> Giving the central place gcc takes, does gcc have the
> (moral not legal) obligation to make good on an implied promise
> to function as a "portable assembler"?

I'm not sure what that means.

> What do you say about the complaints of Anton Ertl, that gcc
> doesn't, as set Forth in his document?:
>
> http://www.google.com/url?q=http%3A%2F%2Fwww.complang.tuwien.ac.at%2Fkps2015%2Fproceedings%2FKPS_2015_submission_29.pdf&sa=D&sntz=1&usg=AFQjCNFzi3tGVat7LrA4FUXiJYWKGaKz1A

For anyone else who wants to read it, here's a shorter link:

http://www.complang.tuwien.ace.at/kps2015/proceedings/KPS_2015_submission_29.pdf

I haven't read it myself.  I might later.

[...]

> Another weak example is that in implementing Forth one wants to
> compare raw pointers.
> void *memmove(void *dest, const void *src, size_t n) {
>     if (dest<src)
>         memcpy_pos_stride(dest,src,n);
>     else
>         memcpy_neg_stride(dest,src,n);
> }
>
> This is expressible in C without resorting to undefined behaviour.

Did you omit a "not" in that sentence?

Evaluating (dest<src) has undefined behavior if dest and src don't
point into the same object (or just past the end of it).

You could check for overlap (without necessarily detecting which
pointer is "less than" the other one) using equality comparisons
in a loop.  There's no way to implement memmove() efficiently in
portable C.  I'm sympathetic to arguments that there should be,
but there isn't.

[...]

-- 
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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Re: OT: One of Anton's papers makes Hacker News Albert van der Horst <albert@spenarnc.xs4all.nl> - 2016-03-13 12:27 +0000
  Re: OT: One of Anton's papers makes Hacker News raltbos@xs4all.nl (Richard Bos) - 2016-03-13 13:50 +0000
    Re: OT: One of Anton's papers makes Hacker News Albert van der Horst <albert@spenarnc.xs4all.nl> - 2016-03-13 19:52 +0000
      Re: OT: One of Anton's papers makes Hacker News Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-03-13 16:08 -0400
      Re: OT: One of Anton's papers makes Hacker News Keith Thompson <kst-u@mib.org> - 2016-03-13 13:40 -0700
        Re: OT: One of Anton's papers makes Hacker News Bernd Paysan <bernd.paysan@gmx.de> - 2016-03-14 00:41 +0000
          Re: OT: One of Anton's papers makes Hacker News Keith Thompson <kst-u@mib.org> - 2016-03-13 18:23 -0700
            Re: OT: One of Anton's papers makes Hacker News Bernd Paysan <bernd.paysan@gmx.de> - 2016-03-14 02:59 +0000
              Re: OT: One of Anton's papers makes Hacker News Keith Thompson <kst-u@mib.org> - 2016-03-13 20:29 -0700
                Re: OT: One of Anton's papers makes Hacker News Bernd Paysan <bernd.paysan@gmx.de> - 2016-03-14 22:44 +0000
                Re: OT: One of Anton's papers makes Hacker News Keith Thompson <kst-u@mib.org> - 2016-03-14 16:23 -0700
                Re: OT: One of Anton's papers makes Hacker News Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2016-03-14 23:55 +0000
                Re: OT: One of Anton's papers makes Hacker News Keith Thompson <kst-u@mib.org> - 2016-03-14 17:19 -0700
                Re: OT: One of Anton's papers makes Hacker News Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-03-15 03:06 -0700
                Re: OT: One of Anton's papers makes Hacker News Keith Thompson <kst-u@mib.org> - 2016-03-15 08:47 -0700
                Re: OT: One of Anton's papers makes Hacker News Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-03-15 11:59 -0400
                Re: OT: One of Anton's papers makes Hacker News Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-03-15 09:34 -0700
                Re: OT: One of Anton's papers makes Hacker News supercat@casperkitty.com - 2016-03-15 11:17 -0700
                Re: OT: One of Anton's papers makes Hacker News Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-15 12:41 -0400
                Re: OT: One of Anton's papers makes Hacker News Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-03-15 10:54 -0700
                Re: OT: One of Anton's papers makes Hacker News supercat@casperkitty.com - 2016-03-15 11:18 -0700
                Re: OT: One of Anton's papers makes Hacker News Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-15 14:42 -0400
                Re: OT: One of Anton's papers makes Hacker News supercat@casperkitty.com - 2016-03-15 11:54 -0700
                Re: OT: One of Anton's papers makes Hacker News Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-15 16:11 -0400
                Re: OT: One of Anton's papers makes Hacker News Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-15 16:13 -0400
                Re: OT: One of Anton's papers makes Hacker News Robert Wessel <robertwessel2@yahoo.com> - 2016-03-15 16:18 -0500
                Re: OT: One of Anton's papers makes Hacker News Stephen Sprunk <stephen@sprunk.org> - 2016-03-15 15:37 -0500
                Re: OT: One of Anton's papers makes Hacker News Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-15 16:42 -0400
                Re: OT: One of Anton's papers makes Hacker News Robert Wessel <robertwessel2@yahoo.com> - 2016-03-14 19:26 -0500
                Re: OT: One of Anton's papers makes Hacker News Bernd Paysan <bernd.paysan@gmx.de> - 2016-03-15 00:48 +0000
                Re: OT: One of Anton's papers makes Hacker News Keith Thompson <kst-u@mib.org> - 2016-03-14 22:30 -0700
                Re: OT: One of Anton's papers makes Hacker News anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-03-15 07:23 +0000
                Re: OT: One of Anton's papers makes Hacker News Albert van der Horst <albert@spenarnc.xs4all.nl> - 2016-03-15 10:09 +0000
                Re: OT: One of Anton's papers makes Hacker News Richard Damon <Richard@Damon-Family.org> - 2016-03-15 08:19 -0400
                Re: OT: One of Anton's papers makes Hacker News Keith Thompson <kst-u@mib.org> - 2016-03-15 08:56 -0700
                Re: OT: One of Anton's papers makes Hacker News Albert van der Horst <albert@spenarnc.xs4all.nl> - 2016-03-15 19:33 +0000
                Re: OT: One of Anton's papers makes Hacker News Rosario19 <Ros@invalid.invalid> - 2016-03-17 09:46 +0100
                Re: OT: One of Anton's papers makes Hacker News Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-17 09:37 -0400
                Re: OT: One of Anton's papers makes Hacker News Rosario19 <Ros@invalid.invalid> - 2016-03-17 18:40 +0100
                Re: OT: One of Anton's papers makes Hacker News Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-17 13:53 -0400
                Re: OT: One of Anton's papers makes Hacker News supercat@casperkitty.com - 2016-03-17 11:53 -0700
                Re: OT: One of Anton's papers makes Hacker News Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-17 19:58 -0400
                Re: OT: One of Anton's papers makes Hacker News Rosario19 <Ros@invalid.invalid> - 2016-03-17 18:37 +0100
                Re: OT: One of Anton's papers makes Hacker News Albert van der Horst <albert@spenarnc.xs4all.nl> - 2016-03-18 14:36 +0000
                Re: OT: One of Anton's papers makes Hacker News Tim Rentsch <txr@alumni.caltech.edu> - 2016-03-18 08:14 -0700
              Re: OT: One of Anton's papers makes Hacker News David Brown <david.brown@hesbynett.no> - 2016-03-14 09:17 +0100
                Re: OT: One of Anton's papers makes Hacker News supercat@casperkitty.com - 2016-03-14 14:14 -0700
                Re: OT: One of Anton's papers makes Hacker News Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-03-14 14:26 -0700
                Re: OT: One of Anton's papers makes Hacker News supercat@casperkitty.com - 2016-03-14 14:46 -0700
                Re: OT: One of Anton's papers makes Hacker News David Brown <david.brown@hesbynett.no> - 2016-03-15 10:39 +0100
                Re: OT: One of Anton's papers makes Hacker News David Brown <david.brown@hesbynett.no> - 2016-03-15 10:38 +0100
                Re: OT: One of Anton's papers makes Hacker News supercat@casperkitty.com - 2016-03-15 07:47 -0700
                Re: OT: One of Anton's papers makes Hacker News Bernd Paysan <bernd.paysan@gmx.de> - 2016-03-14 22:56 +0000
                Re: OT: One of Anton's papers makes Hacker News Robert Wessel <robertwessel2@yahoo.com> - 2016-03-14 20:00 -0500
                Re: OT: One of Anton's papers makes Hacker News David Brown <david.brown@hesbynett.no> - 2016-03-15 11:22 +0100
            Re: OT: One of Anton's papers makes Hacker News Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-03-14 00:43 -0700
              Re: OT: One of Anton's papers makes Hacker News Richard Heathfield <rjh@cpax.org.uk> - 2016-03-14 08:06 +0000
            Re: OT: One of Anton's papers makes Hacker News supercat@casperkitty.com - 2016-03-14 14:01 -0700
              Re: OT: One of Anton's papers makes Hacker News Keith Thompson <kst-u@mib.org> - 2016-03-14 14:55 -0700
                Re: OT: One of Anton's papers makes Hacker News supercat@casperkitty.com - 2016-03-14 15:17 -0700
                Re: OT: One of Anton's papers makes Hacker News raltbos@xs4all.nl (Richard Bos) - 2016-03-14 22:40 +0000
                Re: OT: One of Anton's papers makes Hacker News Jerry Stuckle <jstucklex@attglobal.net> - 2016-03-14 20:12 -0400
                Re: OT: One of Anton's papers makes Hacker News Keith Thompson <kst-u@mib.org> - 2016-03-14 16:17 -0700
                Re: OT: One of Anton's papers makes Hacker News supercat@casperkitty.com - 2016-03-14 23:28 -0700
                Re: OT: One of Anton's papers makes Hacker News Keith Thompson <kst-u@mib.org> - 2016-03-15 00:05 -0700
                Re: OT: One of Anton's papers makes Hacker News Richard Heathfield <rjh@cpax.org.uk> - 2016-03-15 08:29 +0000
          Re: OT: One of Anton's papers makes Hacker News raltbos@xs4all.nl (Richard Bos) - 2016-03-14 22:38 +0000
      Re: OT: One of Anton's papers makes Hacker News Randy Howard <rhoward.mx@EverybodyUsesIt.com> - 2016-03-14 01:40 -0500
    Re: OT: One of Anton's papers makes Hacker News fir <profesor.fir@gmail.com> - 2016-03-15 09:24 -0700

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