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From: robert.corbett@sun.com
Newsgroups: comp.lang.ada,comp.lang.fortran
Subject: Re: Ada vs Fortran for scientific applications
Date: 29 May 2006 21:55:24 -0700
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Jan Vorbr=FCggen wrote:
> > OK, but say for a certain program it is more efficient to store a
> > complex array with all the real parts followed by all the imaginary
> > parts, and the compiler figured this out.  The "as if" rule would work
> > only if there was no other way for the program/programmer to discover
> > the change.  If the array was in COMMON, EQUIVALENCEd, or passed to an
> > external routine, this optimization most likely couldn't be done.
> > Without any legal way to view the storage association, it would seem
> > possible to do it.
>
> Precisely what I was thinking. So historic baggage is weighing Fortran do=
wn
> in this particular case.

The cases of COMMON and EQUIVALENCE are not a serious problem,
since the compiler can tell if an array is in a common block or an
equivalence group.  Passing the array to an external routine is a
serious problem, but I do not classify passing arrays to external
routines
as historical baggage.

Bob Corbett