I've installed the Sun Studio 12 compiler on atlantis. You can use it by adding /sandbox/software/sun/studio12/install/bin to your path. The current Sun Studio series has deprecated -xarch=v9 and replaced it with -m64. -- Pavan -- Pavan Balaji, Mathematics and Computer Science, Argonne National Laboratory Ph: 630.252.3017 http://www.mcs.anl.gov/~balaji