From: Robert Dewar <robert_dewar@my-deja.com>
Subject: Re: Ada95 Strengths/Weaknesses.
Date: 1999/09/29
Date: 1999-09-29T00:00:00+00:00 [thread overview]
Message-ID: <7str6f$k1d$1@nnrp1.deja.com> (raw)
In-Reply-To: 7sqq0h$8q61@news.cis.okstate.edu
In article <7sqq0h$8q61@news.cis.okstate.edu>,
dvdeug@x8b4e53cd. (David Starner) wrote:
> He basically said that if the Ada compiler did not produce
code
> as small as the C++ compiler, then it was junk, and that GNAT
> in particular would produce the same code ("identical object
> code") as G++.
I will repeat it, if you write identical corresponding source
code in Ada and C++ you will get identical object code. But
you need to know a LOT about both languages to write identical
code. Almost always comparisons are flawed because of casual
assumptions that things that are superficially similar are the
same.
For example, computing a sqrt in C++ is not the same as
computing a sqrt in Ada, because in the latter case but not
the former case there are rules about precision, handling of
minus zeroes etc, which are just ignored in the former case.
<< I was merely calling him on that.>>
But I am not sure you understood what I wrote, your posts so
far indicate otherwise. For example, you apparently in your
first attempt used different random number generators. That
of course renders the comparison completely useless, since now
you are simply measuring the size/performance of two random
number generators, and that has nothing whatsoever to do with
a language comparison.
In fact the comparison you are attempting to do is extremely
difficult and requires, as I note, a very extensive knowledge
of the two languages.
Now of course people writing casually without this knowledge
will see varied results, and they may see one thing or they
may see another, depending on somewhat arbitrary decisions
they have made.
If you like post just an excerpt from your program, e.g. one
procedure written in Ada vs one function written in C++, and
it may be illuminating. If the object code is not the same, then
they clearly are not identical in the sense I am talking about
above, so it may be instructive to explain WHY they are not
identical
Robert Dewar
Sent via Deja.com http://www.deja.com/
Before you buy.
next prev parent reply other threads:[~1999-09-29 0:00 UTC|newest]
Thread overview: 87+ messages / expand[flat|nested] mbox.gz Atom feed top
1999-09-27 0:00 Ada95 Strengths/Weaknesses the middleman
1999-09-27 0:00 ` Steve Doiel
1999-09-27 0:00 ` J. David Bryan
1999-09-27 0:00 ` David Starner
1999-09-28 0:00 ` Robert Dewar
1999-09-28 0:00 ` David Starner
1999-09-28 0:00 ` Robert Dewar
1999-09-28 0:00 ` Ray Blaak
1999-09-28 0:00 ` David Starner
1999-09-29 0:00 ` Robert A Duff
1999-09-28 0:00 ` the middleman
1999-09-28 0:00 ` Robert Dewar
1999-09-28 0:00 ` Code size of Ada ? was " Alfred Hilscher
1999-09-28 0:00 ` Gautier
1999-09-28 0:00 ` David Botton
1999-09-29 0:00 ` Robert Dewar
1999-09-29 0:00 ` Alfred Hilscher
1999-09-29 0:00 ` Robert Dewar
1999-09-30 0:00 ` Alfred Hilscher
1999-09-30 0:00 ` Robert Dewar
1999-09-30 0:00 ` Gautier
1999-09-29 0:00 ` Larry Kilgallen
1999-09-29 0:00 ` Robert Dewar
1999-09-29 0:00 ` Alfred Hilscher
1999-09-29 0:00 ` Ted Dennison
1999-09-29 0:00 ` Robert Dewar
1999-09-30 0:00 ` Alfred Hilscher
1999-09-30 0:00 ` Robert Dewar
1999-09-30 0:00 ` Ehud Lamm
1999-09-30 0:00 ` Robert Dewar
[not found] ` <7t2e1l$lqt2@ftp.kvaerner.com>
[not found] ` <37F91D6E.58685CFE@mitre.org>
[not found] ` <7tf7uo$h2b$1@nnrp1.deja.com>
[not found] ` <37FBA978.A86762F1@mitre.org>
1999-10-18 0:00 ` Robert Dewar
1999-10-19 0:00 ` Code size of Ada ? Robert I. Eachus
[not found] ` <7tf7uo <37FBA978.A86762F1@mitre.org>
[not found] ` <5OkO3.2$1e.659@typhoon.nyu.edu>
1999-10-19 0:00 ` Code size of Ada ? was Re: Ada95 Strengths/Weaknesses Robert I. Eachus
1999-09-30 0:00 ` tmoran
1999-09-30 0:00 ` Gautier
1999-09-30 0:00 ` Robert Dewar
1999-09-30 0:00 ` Robert Dewar
1999-09-30 0:00 ` Robert Dewar
1999-09-29 0:00 ` Gautier
1999-09-29 0:00 ` Ed Falis
1999-09-29 0:00 ` tmoran
1999-09-29 0:00 ` Gautier
1999-09-30 0:00 ` Robert Dewar
1999-09-29 0:00 ` Robert Dewar
1999-09-28 0:00 ` GNAT listing file default names (was: Ada95 Strengths/Weaknesses) Larry Kilgallen
1999-09-28 0:00 ` Gautier
1999-09-29 0:00 ` Robert Dewar
1999-09-29 0:00 ` Robert Dewar
1999-09-29 0:00 ` Larry Kilgallen
1999-09-29 0:00 ` Robert Dewar
1999-09-29 0:00 ` Larry Kilgallen
1999-09-30 0:00 ` Robert Dewar
1999-09-28 0:00 ` Ada95 Strengths/Weaknesses David Starner
1999-09-28 0:00 ` Robert Dewar
1999-09-28 0:00 ` David Starner
1999-09-29 0:00 ` Robert Dewar
1999-09-30 0:00 ` Pragma (was Re: Ada95 Strengths/Weaknesses.) Preben Randhol
1999-09-30 0:00 ` Preben Randhol
1999-09-28 0:00 ` Ada95 Strengths/Weaknesses Robert Dewar
1999-09-28 0:00 ` Ted Dennison
1999-09-28 0:00 ` Simon Wright
1999-09-28 0:00 ` Gautier
1999-09-28 0:00 ` David Starner
1999-09-29 0:00 ` Robert Dewar [this message]
1999-09-28 0:00 ` Ed Falis
1999-09-28 0:00 ` David Starner
1999-09-29 0:00 ` Robert Dewar
1999-09-28 0:00 ` p.obry
1999-09-28 0:00 ` David Starner
1999-09-28 0:00 ` Richard D Riehle
1999-09-27 0:00 ` Marin David Condic
1999-09-27 0:00 ` Hyman Rosen
1999-09-28 0:00 ` Robert Dewar
1999-09-28 0:00 ` Preben Randhol
1999-09-28 0:00 ` bill
1999-09-27 0:00 ` Aidan Skinner
1999-09-28 0:00 ` Steve Doiel
1999-09-28 0:00 ` Larry Kilgallen
1999-09-28 0:00 ` Preben Randhol
1999-09-28 0:00 ` Ed Falis
1999-09-28 0:00 ` Hyman Rosen
1999-09-28 0:00 ` Ed Falis
1999-09-28 0:00 ` Preben Randhol
1999-09-28 0:00 ` Geoff Bull
1999-09-29 0:00 ` the middleman
1999-09-29 0:00 ` Robert A Duff
1999-09-28 0:00 ` Geoff Bull
replies disabled
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox