/usr/share/gocode/src/ is in golang-github-cznic-mathutil-dev 0.0~git20150605.0.a804f0f-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/gocode/src/github.com/
/usr/share/gocode/src/github.com/cznic/
/usr/share/gocode/src/github.com/cznic/mathutil/
/usr/share/gocode/src/github.com/cznic/mathutil/all_test.go
/usr/share/gocode/src/github.com/cznic/mathutil/bits.go
/usr/share/gocode/src/github.com/cznic/mathutil/envelope.go
/usr/share/gocode/src/github.com/cznic/mathutil/example/
/usr/share/gocode/src/github.com/cznic/mathutil/example/example.go
/usr/share/gocode/src/github.com/cznic/mathutil/example2/
/usr/share/gocode/src/github.com/cznic/mathutil/example2/example2.go
/usr/share/gocode/src/github.com/cznic/mathutil/example3/
/usr/share/gocode/src/github.com/cznic/mathutil/example3/example3.go
/usr/share/gocode/src/github.com/cznic/mathutil/example4/
/usr/share/gocode/src/github.com/cznic/mathutil/example4/main.go
/usr/share/gocode/src/github.com/cznic/mathutil/ff/
/usr/share/gocode/src/github.com/cznic/mathutil/ff/main.go
/usr/share/gocode/src/github.com/cznic/mathutil/mathutil.go
/usr/share/gocode/src/github.com/cznic/mathutil/mersenne/
/usr/share/gocode/src/github.com/cznic/mathutil/mersenne/all_test.go
/usr/share/gocode/src/github.com/cznic/mathutil/mersenne/mersenne.go
/usr/share/gocode/src/github.com/cznic/mathutil/permute.go
/usr/share/gocode/src/github.com/cznic/mathutil/primes.go
/usr/share/gocode/src/github.com/cznic/mathutil/rat.go
/usr/share/gocode/src/github.com/cznic/mathutil/rnd.go
/usr/share/gocode/src/github.com/cznic/mathutil/tables.go
/usr/share/gocode/src/github.com/cznic/mathutil/test_deps.go