Newsgroups: comp.parallel.mpi
From: wcs@win233.nas.nasa.gov (William C. Saphir)
Subject: Re: Dynamic memory allocation in Fortran
Organization: NAS/NASA Ames Research Center
Date: 21 Sep 1996 20:45:51 -0700
Message-ID: <v3tpw3fcivk.fsf@win233.nas.nasa.gov>


> What I wonder, though, is why use Cray pointers instead of F90 pointers?
> I would think F90 pointers would be more standard. (It's what we have
> choosen to go with for our F-- work).

My understanding of this issue is that creating F90 pointers requires
compiler support, or at least knowledge of compiler
internals. Normally the only way to allocate space for an F90 pointer
is with the allocate() intrinsic.  This is because an F90 pointer is
not just an address in memory, but a fairly complex object. Cray
pointers, on the other hand, are very much like C pointers. They are
not integers, but look a lot like them and don't have all the extra
baggage of F90 pointers. 

Is there an easy way to use F90 pointers that I'm not seeing?

Bill


