进程异常退出后 Go Channel中未消费的消息怎么办？

func main() {
    ch := make(chan int)

    go func() {
        defer close(ch)

        for i := 0; i < 10; i++ {
            ch <- i
        }
    }()

    for {
        select {
        case msg, ok := <-ch:
            if !ok {
                return
            }
            fmt.Println(msg)
        }
    }
}

func main() {
    ch := make(chan int)
    var wg sync.WaitGroup

    wg.Add(1)
    go func() {
        defer wg.Done()

        for i := 0; i < 10; i++ {
            ch <- i
        }
    }()

    go func() {
        wg.Wait()
        close(ch)
    }()

    for msg := range ch {
        fmt.Println(msg)
    }
}

func main() {
    ctx, cancel := context.WithCancel(context.Background())
    ch := make(chan int)

    go func() {
        defer close(ch)

        for i := 0; i < 10; i++ {
            select {
            case ch <- i:
            case <-ctx.Done():
                return
            }
        }
    }()

    for {
        select {
        case msg, ok := <-ch:
            if !ok {
                return
            }
            fmt.Println(msg)
        case <-ctx.Done():
            return
        }
    }

    cancel()
}