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Re: Hash table implementation.

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Am 08/19/2011 10:17 AM, schrieb Herbert Rosenau:
> On Fri, 12 Aug 2011 22:08:31 UTC, Jens Gustedt <Jens.Gustedt@loria.fr>
> wrote:
> 
>> Am 08/12/2011 08:55 AM, schrieb lolzy@live.nl:
>>> * Why shouldn't I use the register keyword for loop variables?
>>
>> The register keyword is just a misnomer and has not much to do with the
>> registers of your CPU. Its only purpose nowadays is that you are not
>> allowed to take the address of such a variable such that it *may* be
>> implemented more efficiently (e.g a CPU register or an immediate).
> 
> No.

How is that, "no"? Do you question the fact that one is not allowed to
take the address of a variable with register storage class?

> register is a relict from K&R1. At that time it was the istruction
> to the compiler to place the variable into a CPU-register if one is 
> available.

The naming as "register" is a relict, yes.

> But since then there are more than 20 years gone. More moder compilers
> are more intelligent than the mayority of programmers using them. They
> can better decide which one should be in a register. So it will ignore
> the keyword.

With that opinion, you are not at all in allignement with the current
C standard:

 C99> The intended use of the restrict qualifier (like the register storage
 C99> class) is to promote optimization, ...

and AFAIR the new proposal C1x stays with this.

As a the restrict keyword, register is a constract between the
programmer and the compiler that helps to promote certain types of
optimizations. Not more and not less.

Jens

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Hash table implementation. lolzy@live.nl - 2011-08-11 10:43 -0700
  Re: Hash table implementation. China Blue Tip Wrench <chine.bleu@yahoo.com> - 2011-08-11 11:25 -0700
  Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-11 11:49 -0700
    Re: Hash table implementation. Ralf Damaschke <rwspam@gmx.de> - 2011-08-11 20:02 +0000
  Re: Hash table implementation. Ike Naar <ike@sverige.freeshell.org> - 2011-08-11 22:02 +0000
  Re: Hash table implementation. "Scott Fluhrer" <sfluhrer@ix.netcom.com> - 2011-08-11 18:14 -0400
    Re: Hash table implementation. lolzy@live.nl - 2011-08-11 23:55 -0700
      Re: Hash table implementation. lolzy@live.nl - 2011-08-12 01:38 -0700
      Re: Hash table implementation. Nobody <nobody@nowhere.com> - 2011-08-12 09:47 +0100
        Re: Hash table implementation. tom st denis <tom@iahu.ca> - 2011-08-12 06:15 -0700
          Re: Hash table implementation. James Kuyper <jameskuyper@verizon.net> - 2011-08-12 11:34 -0400
            Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-12 08:50 -0700
              Re: Hash table implementation. James Kuyper <jameskuyper@verizon.net> - 2011-08-12 12:24 -0400
          Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-12 08:38 -0700
            Re: Hash table implementation. tom st denis <tom@iahu.ca> - 2011-08-12 10:17 -0700
              Re: Hash table implementation. James Kuyper <jameskuyper@verizon.net> - 2011-08-12 13:54 -0400
                Re: Hash table implementation. tom st denis <tom@iahu.ca> - 2011-08-12 11:30 -0700
                Re: Hash table implementation. Seebs <usenet-nospam@seebs.net> - 2011-08-12 20:39 +0000
                Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-12 14:08 -0700
            Re: Hash table implementation. gordonb.4sxmx@burditt.org (Gordon Burditt) - 2011-08-12 20:04 -0500
              Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-12 18:40 -0700
                Re: Hash table implementation. Harald van Dijk <truedfx@gmail.com> - 2011-08-13 12:59 -0700
              Re: Hash table implementation. Seebs <usenet-nospam@seebs.net> - 2011-08-13 02:34 +0000
      Re: Hash table implementation. Ike Naar <ike@iceland.freeshell.org> - 2011-08-12 11:13 +0000
      Re: Hash table implementation. Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-08-12 07:24 -0400
      Re: Hash table implementation. Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-08-12 09:27 -0600
      Re: Hash table implementation. Seebs <usenet-nospam@seebs.net> - 2011-08-12 18:37 +0000
      Re: Hash table implementation. Jens Gustedt <Jens.Gustedt@loria.fr> - 2011-08-13 00:08 +0200
        Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-12 15:26 -0700
          Re: Hash table implementation. Jens Gustedt <Jens.Gustedt@loria.fr> - 2011-08-13 15:11 +0200
            Re: Hash table implementation. Keith Thompson <kst-u@mib.org> - 2011-08-13 11:38 -0700
              Re: Hash table implementation. Jens Gustedt <Jens.Gustedt@loria.fr> - 2011-08-13 21:03 +0200
        Re: Hash table implementation. "Herbert Rosenau" <os2guy@pc-rosenau.de> - 2011-08-19 08:17 +0000
          Re: Hash table implementation. Jens Gustedt <jens.gustedt@loria.fr> - 2011-08-19 13:29 +0200
          Re: Hash table implementation. Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-08-19 14:35 +0300
  Re: Hash table implementation. Michael Angelo Ravera <maravera@prodigy.net> - 2011-08-12 02:54 -0700
  Re: Hash table implementation. Rui Maciel <rui.maciel@gmail.com> - 2011-08-13 23:11 +0100
    Re: Hash table implementation. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-08-14 00:56 +0100
      Re: Hash table implementation. lolzy@live.nl - 2011-08-14 00:11 -0700
        Re: Hash table implementation. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-08-14 11:57 +0100

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