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Re: Register storage type

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Seebs <usenet-nospam@seebs.net> writes:
> On 2011-05-12, Keith Thompson <kst-u@mib.org> wrote:
>> Ah, but "register" can be applied only to block-scope.  Presumably
>> any decent optimizing compiler can already tell that a block-scope
>> variable's address is never taken, just by analyzing the code.
>
> I try not to make assumptions about whether things are "decent".  The
> world continues to surprise and astound me, even after all these years.
>
> Remember:  The phrase "no one would be dumb enough to..." does not come
> at the beginning of any true statement.

Ok, but your point (that "register" can help an optimizer by telling
it that an object's address is never taken) is relevant only for a
compiler that (a) is too dumb to detect by itself that a block-scope
object's address is never taken, but (b) is smart enough to make
good use of the information.

Conceivable, but not the way I'd bet -- and I wouldn't clutter my
code with otherwise superfluous "register" specifiers to cater to
such compilers without a very good reason.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Nokia
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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Register storage type Free Willy <nospam@nospam.com> - 2011-05-12 20:55 +0000
  Re: Register storage type Kenneth Brody <kenbrody@spamcop.net> - 2011-05-12 17:02 -0400
    Re: Register storage type Free Willy <nospam@nospam.com> - 2011-05-12 21:13 +0000
      Re: Register storage type Angel <angel+news@spamcop.net> - 2011-05-12 21:20 +0000
      Re: Register storage type Keith Thompson <kst-u@mib.org> - 2011-05-12 14:27 -0700
        Re: Register storage type Kenneth Brody <kenbrody@spamcop.net> - 2011-05-13 13:20 -0400
          Re: Register storage type Free Willy <nospam@nospam.com> - 2011-05-13 21:30 +0000
            Re: Register storage type Keith Thompson <kst-u@mib.org> - 2011-05-13 15:50 -0700
              Different languages (Was: Register storage type) gazelle@shell.xmission.com (Kenny McCormack) - 2011-05-14 08:58 +0000
                Re: Different languages (Was: Register storage type) Dr Nick <3-nospam@temporary-address.org.uk> - 2011-05-14 10:09 +0100
              Re: Register storage type Free Willy <nospam@nospam.com> - 2011-05-14 21:27 +0000
                Re: Register storage type Ian Collins <ian-news@hotmail.com> - 2011-05-15 09:55 +1200
                Re: Register storage type Keith Thompson <kst-u@mib.org> - 2011-05-14 16:46 -0700
                Re: Register storage type Jens <jens.gustedt@gmail.com> - 2011-05-15 10:08 -0700
                Re: Register storage type James Kuyper <jameskuyper@verizon.net> - 2011-05-15 14:09 -0400
                Re: Register storage type David Thompson <dave.thompson2@verizon.net> - 2011-05-19 01:50 -0400
                Re: Register storage type Stephen Sprunk <stephen@sprunk.org> - 2011-05-15 00:27 -0500
                Re: Register storage type Angel <angel+news@spamcop.net> - 2011-05-15 12:56 +0000
                Re: Register storage type Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-05-15 11:54 -0400
                Re: Register storage type Seebs <usenet-nospam@seebs.net> - 2011-05-15 17:43 +0000
                Re: Register storage type Tim Rentsch <txr@alumni.caltech.edu> - 2011-05-18 23:37 -0700
                Re: Register storage type Seebs <usenet-nospam@seebs.net> - 2011-05-19 14:37 +0000
                Drift: Linguistics (was Re: Register storage type) Kenneth Brody <kenbrody@spamcop.net> - 2011-05-19 13:17 -0400
                Re: Register storage type Tim Rentsch <txr@alumni.caltech.edu> - 2011-05-19 11:05 -0700
                Re: Register storage type Seebs <usenet-nospam@seebs.net> - 2011-05-19 19:08 +0000
                Re: Register storage type Tim Rentsch <txr@alumni.caltech.edu> - 2011-05-24 00:39 -0700
                Re: Register storage type Ian Collins <ian-news@hotmail.com> - 2011-05-20 07:46 +1200
                Re: Register storage type Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-05-19 22:37 -0400
                Re: Register storage type Michael Press <rubrum@pacbell.net> - 2011-05-25 12:57 -0700
                Re: Register storage type pete <pfiland@mindspring.com> - 2011-05-15 09:09 -0400
      Re: Register storage type Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-05-12 21:57 -0400
  Re: Register storage type Angel <angel+news@spamcop.net> - 2011-05-12 21:14 +0000
    Re: Register storage type gordonb.unc3q@burditt.org (Gordon Burditt) - 2011-05-13 07:49 -0500
  Re: Register storage type Keith Thompson <kst-u@mib.org> - 2011-05-12 14:20 -0700
    Re: Register storage type Seebs <usenet-nospam@seebs.net> - 2011-05-12 21:59 +0000
      Re: Register storage type BGB <cr88192@hotmail.com> - 2011-05-12 15:50 -0700
      Re: Register storage type Keith Thompson <kst-u@mib.org> - 2011-05-12 15:49 -0700
        Re: Register storage type Seebs <usenet-nospam@seebs.net> - 2011-05-12 23:19 +0000
          Re: Register storage type Keith Thompson <kst-u@mib.org> - 2011-05-12 16:29 -0700
            Re: Register storage type Seebs <usenet-nospam@seebs.net> - 2011-05-13 00:15 +0000
  Re: Register storage type Columbus sailed the ocean China Blue <chine.bleu@yahoo.com> - 2011-05-12 15:24 -0700
  Re: Register storage type Peter Nilsson <airia@acay.com.au> - 2011-05-12 17:39 -0700

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