The GNU Fortran compiler installed on the Astro system has a bug which is exhibited when you use it to build scipy. Fix this by installing the most recent version of gfortran that is packaged and available on the R website. Do not install the version from the HPC on OS X website (or any GCC packages from that site). They are buggy.
By default the R gfortran package installs itself into /usr/local,
which you don’t have permission to write to. You should therefore
install it in ~/usr/local, or some other directory in your home
directory. To do this:
Mount the disk image you download.
cd ~ in Terminal
Run this command:
pax -zr < /Volumes/GNU\ Fortran\ 4.2.3/gfortran.pkg/Contents/Archive.pax.gz
You should now have a directory ~/usr/local full of
gfortran-related stuff. Add ~/usr/local/bin to your shell’s PATH.
Make sure it appears in the path ahead of /usr/local/bin or you
will continue to use the buggy Fortran compiler. If you use Fortran
for anything other than compiling scipy then make sure you understand
the implications of this.