From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham
	autolearn_force=no version=3.4.4
X-Google-Thread: 103376,c4cb2c432feebd9d
X-Google-Thread: 1094ba,c4cb2c432feebd9d
X-Google-Thread: 101deb,15c6ed4b761968e6
X-Google-Attributes: gid103376,gid1094ba,gid101deb,public
X-Google-Language: ENGLISH,ASCII-7-bit
Path: 
 g2news2.google.com!news4.google.com!sn-xt-sjc-15!sn-xt-sjc-01!sn-post-sjc-01!supernews.com!news.supernews.com!nospam
From: nospam@see.signature (Richard E Maine)
Newsgroups: comp.lang.ada,comp.lang.fortran,comp.lang.pl1
Subject: Re: Ada vs Fortran for scientific applications
Date: Tue, 11 Jul 2006 08:55:41 -0700
Organization: NASA Dryden
Message-ID: <1hiayuk.4mm8dzknzt0nN%nospam@see.signature>
References: <mubcg.13522$fb2.853@newssvr27.news.prodigy.net>
 <epcs4e.qb8.ln@hunter.axlog.fr> <tHkcg.6937$kR6.484@trnddc05>
 <0ugu4e.4i7.ln@hunter.axlog.fr>
 <PkHcg.90575$Fs1.7198@bgtnsc05-news.ops.worldnet.att.net>
 <To_cg.10095$S7.4017@news-server.bigpond.net.au>
 <%P_cg.155733$eR6.26337@bgtnsc04-news.ops.worldnet.att.net>
 <6H9dg.10258$S7.9150@news-server.bigpond.net.au>
 <XVadg.76594$_S7.45873@newssvr14.news.prodigy.com>
 <1hfv5wb.1x4ab1tbdzk7eN%nospam@see.signature>
 <pan.2006.05.25.12.11.52.919554@linuxchip.demon.co.uk.uk.uk>
 <2006052509454116807-gsande@worldnetattnet>
 <R%dsg.63336$fb2.7555@newssvr27.news.prodigy.net>
 <bFesg.111860$mF2.27790@bgtnsc04-news.ops.worldnet.att.net>
 <1kzktalo9krea$.z8n9wev45xct$.dlg@40tude.net>
 <z9Dsg.2740$tE5.2374@news-server.bigpond.net.au>
 <pPHsg.46977$VE1.46332@newssvr14.news.prodigy.com> <kROsg.7$Pg1.2@fe11.lga>
 <_5idnW0Lk4kxXS7ZnZ2dnUVZ_oOdnZ2d@comcast.com>
User-Agent: MacSOUP/2.7 (Mac OS X version 10.4.7)
X-Complaints-To: abuse@supernews.com
Xref: g2news2.google.com comp.lang.ada:5618 comp.lang.fortran:11945
 comp.lang.pl1:1985
Date: 2006-07-11T08:55:41-07:00
List-Id: <comp.lang.ada>

glen herrmannsfeldt <gah@ugcs.caltech.edu> wrote:

> John W. Kennedy wrote:
> 
> > (Java is the only language I know of that will actually fail the compile
> > unless it /knows/ that every variable is initialized before use in every
> > possible path.)
> 
> I am not sure what the language specification says, but Sun compilers
> do that.  (Note: for scalars only, not arrays.)

I don't believe you. Reread what John actually wrote instead of what you
were probably thinking about. Do you really claim that the Sun compiler
will "fail compilation" (which is not the same thing as give a warning)
if it does not "know" that every scalar variable is set before use in
every possible path.

An awful lot of Fortran codes would fail compilation in that case -
enough of them that Sun would feel the backlash rather strongly. It
would also violate the Fortran standard, as those codes are perfectly
conforming to the Fortran standard, which only requires that the
variables be defined when they are actually referenced (i.e. in the path
that is taken - not in some other path that is staticaally possible, but
is not taken).

That Sun might have a warning, I could believe (though it expect such a
warning to be verbose enough that few people would use it). I could also
even more believe that Sun might fail compilation if it could prove at
compile time that a variable would be used without being defined. But
neither of those are equivalent to what John said.

-- 
Richard Maine                     | Good judgment comes from experience;
email: my first.last at org.domain| experience comes from bad judgment.
org: nasa, domain: gov            |       -- Mark Twain