/usr/share/go-1.6/src/sync/ is in golang-1.6-src 1.6.1-0ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/go-1.6/src/sync/atomic/
/usr/share/go-1.6/src/sync/atomic/64bit_arm.go
/usr/share/go-1.6/src/sync/atomic/asm_386.s
/usr/share/go-1.6/src/sync/atomic/asm_amd64.s
/usr/share/go-1.6/src/sync/atomic/asm_amd64p32.s
/usr/share/go-1.6/src/sync/atomic/asm_arm.s
/usr/share/go-1.6/src/sync/atomic/asm_arm64.s
/usr/share/go-1.6/src/sync/atomic/asm_darwin_arm.s
/usr/share/go-1.6/src/sync/atomic/asm_freebsd_arm.s
/usr/share/go-1.6/src/sync/atomic/asm_linux_arm.s
/usr/share/go-1.6/src/sync/atomic/asm_mips64x.s
/usr/share/go-1.6/src/sync/atomic/asm_nacl_arm.s
/usr/share/go-1.6/src/sync/atomic/asm_netbsd_arm.s
/usr/share/go-1.6/src/sync/atomic/asm_openbsd_arm.s
/usr/share/go-1.6/src/sync/atomic/asm_ppc64x.s
/usr/share/go-1.6/src/sync/atomic/asm_s390x.s
/usr/share/go-1.6/src/sync/atomic/atomic_linux_arm_test.go
/usr/share/go-1.6/src/sync/atomic/atomic_test.go
/usr/share/go-1.6/src/sync/atomic/doc.go
/usr/share/go-1.6/src/sync/atomic/export_linux_arm_test.go
/usr/share/go-1.6/src/sync/atomic/race.s
/usr/share/go-1.6/src/sync/atomic/value.go
/usr/share/go-1.6/src/sync/atomic/value_test.go
/usr/share/go-1.6/src/sync/cond.go
/usr/share/go-1.6/src/sync/cond_test.go
/usr/share/go-1.6/src/sync/example_test.go
/usr/share/go-1.6/src/sync/export_test.go
/usr/share/go-1.6/src/sync/mutex.go
/usr/share/go-1.6/src/sync/mutex_test.go
/usr/share/go-1.6/src/sync/once.go
/usr/share/go-1.6/src/sync/once_test.go
/usr/share/go-1.6/src/sync/pool.go
/usr/share/go-1.6/src/sync/pool_test.go
/usr/share/go-1.6/src/sync/runtime.go
/usr/share/go-1.6/src/sync/runtime_sema_test.go
/usr/share/go-1.6/src/sync/rwmutex.go
/usr/share/go-1.6/src/sync/rwmutex_test.go
/usr/share/go-1.6/src/sync/waitgroup.go
/usr/share/go-1.6/src/sync/waitgroup_test.go