goReference.go

package main

import (
    "fmt"
    "time"
)

func main() {
	data := testMap2()
	testMap(data)
	time.Sleep(3 * time.Second)
	fmt.Println(data)
}

func testMap(data map[string]string) {
	data["xxx222"] = "xxx"
}

func testMap2() map[string]string {
	data := map[string]string{"xxx":"123"}
	go func(){
		data["xxx333"] = "xxx"
	}()
	return data
}