Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!sgi!bron@bronze.SGI.COM
From: bron@bronze.SGI.COM (Bron Campbell Nelson)
Newsgroups: comp.lang.fortran
Subject: Re: Dubious Fortran Construct
Summary: The VMS manual says no.
Keywords: DO loops; transfer of control
Message-ID: <23185@sgi.SGI.COM>
Date: 10 Dec 88 02:19:29 GMT
References: <22994@sgi.SGI.COM> <467@ur-cc.UUCP> <3677@s.cc.purdue.edu>
Sender: daemon@sgi.SGI.COM
Organization: Silicon Graphics, Inc., Mountain View, CA
Lines: 37

In article <3677@s.cc.purdue.edu>, ags@s.cc.purdue.edu (Dave Seaman) writes:
> In article <467@ur-cc.UUCP> rbr4@uhura.cc.rochester.edu (Roland Roberts) writes:
> >In article <22994@sgi.SGI.COM> bron@bronze.SGI.COM (Bron Campbell Nelson) writes:
> >[problem (deleted): 
> >  multiple do loops terminated by single statement
> >  statement in outer loop (conditionally) branches to loop termination]
> 
> >I've used this construct before, so I was rather surprised by this claim.
> 	[i.e. the claim that the construct is illegal]
> >To test it, I've just typed in this code and our VAX/VMS compiler didn't
> >complain in the slightest.
> 
> The correct test to determine whether it is legal VAX/VMS Fortran is to
> look in the VAX/VMS Fortran manual.  Since I don't have one available, I
> can't answer that one for you except to point out that the fact that "the
> compiler didn't complain" proves nothing.  It may be legal, but only if it
> specifically says so in the DEC manual.  This would then be considered an
> "extension," which means it is not necessarily portable to other Fortran
> environments.
>
I suppose this last comment is true as far as it goes, but I specifically
asked the net whether or not the compiler that you use accepts this construct,
and *also* asked whether or not you believe the construct is legal
(regardless of whether or not the compiler accepted it).

I was a bit surprised by the fact that the VMS compiler accepted it,
obviously my memory is faulty.  What I *do* know for sure is that the
VMS manual specifically declares this construct to be illegal.

As for my 2 cents: my compiler accepts it (but generates incorrect code);
I think it is illegal and should give a syntax error, or at least a
warning.

--
Bron Campbell Nelson      bron@sgi.com
The opinions expressed are not necessarily those of the author's employer,
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those of the author, and are probably not necessary.