Two coroutines write the same term of the slice in parallel. May panic errors occur?

Two coroutines write the same term of the slice in parallel. May panic errors occur?

I not found document about this.

Concurrent reads and writes only cause data disorder, not happen panic error?

import (
    "fmt"
    "strconv"
    "time"
)

func main() {
    arr := []string{"a", "b", "c", "d"}

    // write 1
    go func() {
        for {
            arr[2] = strconv.FormatInt(time.Now().Unix(), 10)
        }
    }()

    // read 1
    go func() {
        for {
            fmt.Println(arr[2])
        }
    }()

    // write 2
    go func() {
        for {
            arr[2] = strconv.FormatInt(time.Now().Unix(), 10)
        }
    }()

    time.Sleep(10 * time.Second)
    return
}