[Ifeffit] a bug when installing demeter

Hi, I am trying to install Demeter on my Mac OX X EI Capitan. After installing MacPorts properly, I run the command, “sudo port install xorg-server demeter”. However, it reports a bug when building libgcc, when the following errors: Error: org.macports.build for port libgcc returned: command execution failed Please see the log file for port libgcc for details: /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_lang_gcc49/libgcc/main.log Error: Unable to upgrade port: 1 Error: Unable to execute port: upgrade ifeffit failed Could you help figure out how I can proceed further? Thanks, Zhenxing