[Beowulf] Quick question... on Fortran

Tom Elken elken at pathscale.com
Thu May 10 15:10:20 PDT 2007

From: "Brian Dobbins" <brian.dobbins at yale.edu>
Subject: Re: [Beowulf] Quick question... on Fortran
To: "Robert G. Brown" <rgb at phy.duke.edu>

 > Using the PGI compilers ...
 > The way to do this is to use the 'mcmodel=medium' option and to promote
 > integers to 8-byte values (for indexing the entries in this array) with
 > '-i8'.

rgb wrote:
> I'd be happy
> for answers for more than one compiler, of course -- I'd guess that e.g.
> pathscale might have a greater capacity than e.g. gfortran than g77
> legacy...

PathScale also supports -mcmodel=medium for large arrays, and I think gcc 
originated that flag name, so I would guess that gfortran supports it as well.

pathf95 also supports the -i8 flag.  If you need a math library to support large 
arrays with i8-type indices, when you download the PathScale version of ACML 
from AMD, you can choose the "PathScale 64-bit Int64" version.  I would guess 
that Intel's MKL also has a version that supports 64bit integer arrays.


~~~~~~~~~~~~~~~~~~~       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Tom Elken                 Manager, Performance Engineering
tom.elken at qlogic.com      QLogic Corporation
650.934.8056              System Interconnect Group

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