3.4-gl2

Obtain the source from:  /afs/slac/g/glast/ground/GLAST_EXT/srcExtLibs/f2c-3.4-gl2.tar.gz

Check out the README in the f2c tarball.  We found on snowleopard that we needed to use the f2c.h that is contained in the f2c tarball rather than running the "make hadd" step which is supposed to copy in the version of f2c.h.  There was an extensive email thread concerning this March, 2011 on the HELPSOFT mailing list.

RHEL7-64

• make hadd but this results in an f2c.h that doesn't match what we have on rhel6-64.. hurmph
• Instead chose to match the f2c.h on rhel6-64, by using the f2c.h that comes with the tarball rather than running "make hadd"
• make