/usr/share/gocode/src/golang.org/x/text/collate/build/ is in golang-golang-x-text-dev 0.0~git20170627.0.6353ef0-1ubuntu2.
This file is owned by root:root, with mode 0o755.
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/usr/share/gocode/src/golang.org/x/text/collate/build/builder.go
/usr/share/gocode/src/golang.org/x/text/collate/build/builder_test.go
/usr/share/gocode/src/golang.org/x/text/collate/build/colelem.go
/usr/share/gocode/src/golang.org/x/text/collate/build/colelem_test.go
/usr/share/gocode/src/golang.org/x/text/collate/build/contract.go
/usr/share/gocode/src/golang.org/x/text/collate/build/contract_test.go
/usr/share/gocode/src/golang.org/x/text/collate/build/order.go
/usr/share/gocode/src/golang.org/x/text/collate/build/order_test.go
/usr/share/gocode/src/golang.org/x/text/collate/build/table.go
/usr/share/gocode/src/golang.org/x/text/collate/build/trie.go
/usr/share/gocode/src/golang.org/x/text/collate/build/trie_test.go