/usr/share/common-lisp/systems/cl-postgres.asd is in cl-postgres 20170403-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/common-lisp/systems/../source/cl-postgres/cl-postgres.asd
/usr/share/common-lisp/systems/../source/cl-postgres/cl-postgres.asd