GoLang JSON Marshal omitempty与非简单类型

Code below is the explanation. The only way I can get omitempty to work with non-simple types is to make that type a pointer.

Is there an alternative solution to this by not using pointers?

CODE NOT WORKING:

type Foo struct {
    Bar Bar `json:"bar,omitempty"`
}

type Bar struct {
    Baz string `json:"baz"`
}

func main() {

    foo := Foo{}

    jsonBytes, _ := json.Marshal(foo)

    fmt.Printf("%s\n", jsonBytes)
}

{"bar":{"baz":""}}

CODE WORKING, BUT NOT WHAT I WANT:

type Foo struct {
    Bar *Bar `json:"bar,omitempty"`
}

type Bar struct {
    Baz string `json:"baz"`
}

func main() {

    foo := Foo{}

    jsonBytes, _ := json.Marshal(foo)

    fmt.Printf("%s\n", jsonBytes)
}

{}