/usr/ is in golang-xi2-x-xz-dev 0.0~git20150926.0.18c6b71-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/gocode/src/xi2.org/x/
/usr/share/gocode/src/xi2.org/x/xz/
/usr/share/
/usr/share/gocode/
/usr/share/gocode/src/
/usr/share/gocode/src/xi2.org/
/usr/share/gocode/src/xi2.org/x/xz/reader.go
/usr/share/gocode/src/xi2.org/x/xz/dec_stream.go
/usr/share/gocode/src/xi2.org/x/xz/dec_bcj.go
/usr/share/gocode/src/xi2.org/x/xz/example_test.go
/usr/share/gocode/src/xi2.org/x/xz/dec_lzma2.go
/usr/share/gocode/src/xi2.org/x/xz/AUTHORS
/usr/share/gocode/src/xi2.org/x/xz/dec_util.go
/usr/share/gocode/src/xi2.org/x/xz/dec_xz.go
/usr/share/gocode/src/xi2.org/x/xz/README.md
/usr/share/gocode/src/xi2.org/x/xz/dec_delta.go
/usr/share/gocode/src/xi2.org/x/xz/doc.go
/usr/share/gocode/src/xi2.org/x/xz/reader_test.go
/usr/share/doc/
/usr/share/doc/golang-xi2-x-xz-dev/
/usr/share/doc/golang-xi2-x-xz-dev/copyright
/usr/share/doc/golang-xi2-x-xz-dev/README.md
/usr/share/doc/golang-xi2-x-xz-dev/changelog.Debian.gz