/usr/share/common-lisp/source/ is in cl-fad 0.7.2-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/common-lisp/source/cl-fad/
/usr/share/common-lisp/source/cl-fad/cl-fad.asd
/usr/share/common-lisp/source/cl-fad/corman.lisp
/usr/share/common-lisp/source/cl-fad/fad.lisp
/usr/share/common-lisp/source/cl-fad/fad.test.lisp
/usr/share/common-lisp/source/cl-fad/load.lisp
/usr/share/common-lisp/source/cl-fad/openmcl.lisp
/usr/share/common-lisp/source/cl-fad/packages.lisp
/usr/share/common-lisp/source/cl-fad/packages.test.lisp
/usr/share/common-lisp/source/cl-fad/path.lisp
/usr/share/common-lisp/source/cl-fad/temporary-files.lisp
/usr/share/common-lisp/source/cl-fad/temporary-files.test.lisp