Error in make dev-requirements

Hi.
when I use make dev-requirements requirements ui-requirements in folder of gopath/src/github.com/brocaar/lora-app-server I get following error:

go get -u The Go Programming Language
The Go Programming Language
…/…/…/golang.org/x/tools/go/internal/gcimporter/bexport.go:212: obj.IsAlias undefined (type *types.TypeName has no field or method IsAlias)
…/…/…/golang.org/x/tools/go/internal/gcimporter/iimport.go:90: undefined: io.SeekCurrent
…/…/…/golang.org/x/tools/go/internal/gcimporter/iimport.go:93: undefined: io.SeekCurrent
…/…/…/golang.org/x/tools/go/internal/gcimporter/iimport.go:169: undefined: io.SeekCurrent
…/…/…/golang.org/x/tools/go/internal/gcimporter/iimport.go:200: r.declReader.Reset undefined (type bytes.Reader has no field or method Reset)
…/…/…/golang.org/x/tools/go/internal/gcimporter/iimport.go:239: r.declReader.Reset undefined (type bytes.Reader has no field or method Reset)
Makefile:58: recipe for target ‘dev-requirements’ failed
make: *** [dev-requirements] Error 2