GO SDK Installing failure

Execute:

go get github.com/couchbase/gocb

Got:

github.com/couchbase/gocb/gocbcore
…/…/couchbase/gocb/gocbcore/agent.go:309:6: error: expected operand
for range routingInfo.servers {
^
…/…/couchbase/gocb/gocbcore/agent.go:309:6: error: expected ‘{’
…/…/couchbase/gocb/gocbcore/agent.go:309:6: error: expected ‘;’ or ‘}’ or newline
…/…/couchbase/gocb/gocbcore/agent.go:315:1: error: expected declaration
}
^
…/…/couchbase/gocb/gocbcore/timerpool.go:8:21: error: reference to undefined identifier ‘sync.Pool’
var globalTimerPool sync.Pool
^
…/…/couchbase/gocb/gocbcore/agent.go:311:3: error: reference to undefined name ‘s’
s.Drain(func(req *memdQRequest) {