Something

% sudo port -v upgrade installed
Error: Unable to open port: can't read "sysroot": no such variable
can't read "portvariants": no such variable
Warning: the following items did not execute (for xrender): org.macports.destroot org.macports.main org.macports.fetch org.macports.extract org.macports.checksum org.macports.patch org.macports.configure org.macports.build
Error: Unable to upgrade port: 1