/usr/ is in cl-trivial-backtrace 20160531-1.
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/usr/share/common-lisp/source/trivial-backtrace/dev/map-backtrace.lisp
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/usr/share/doc/cl-trivial-backtrace/
/usr/share/doc/cl-trivial-backtrace/changelog.Debian.gz
/usr/share/doc/cl-trivial-backtrace/copyright
/usr/share/doc/cl-trivial-backtrace/index.md
/usr/share/common-lisp/systems/trivial-backtrace.asd