Go에서 '치명적인 오류: 동시 맵 읽기 및 맵 쓰기'를 해결하는 방법은 무엇입니까?

var someMap = map[string]string{}
var someMapMutex = sync.RWMutex{}

go func() {
    someMapMutex.Lock()
    someMap["key"] = "value"
    someMapMutex.Unlock()
}()

someMapMutex.RLock()
v, ok := someMap["key"]
someMapMutex.RUnlock()
if !ok {
    fmt.Println("key missing")
    return
}
fmt.Println(v)

var someMap = syncmap.Map{}

go func() {
    someMap.Store("key", "value")
}()

v, ok := someMap.Load("key")
if !ok {
    fmt.Println("key missing")
    return
}
fmt.Println(v)

// Looping over keys is simplified with syncmap
someMap.Range(func(key, value interface{}) bool {
    val, ok := value.(string)
    if !ok {
        return false // Break iteration
    }
    fmt.Println(key, val)
    return true // Continue iteration
})

go run -race server.go