缺陷代码大赏

package main

import (
	"fmt"
	"sync"
)

func route(s []int) {
	fmt.Println(s)
}

func main() {
	batch := 2
	records := []int{1, 2, 3, 4, 5, 6, 7, 8, 9}

	fmt.Println(records[8:])
	pos := 0
	wg := new(sync.WaitGroup)
	wg.Add(1)
	for pos < len(records)-batch {
		wg.Add(1)
		go func() {
			defer wg.Done()
			route(records[pos : pos+batch])
		}()
		pos += batch
	}

	go func() {
		defer wg.Done()
		route(records[pos:])
	}()

	wg.Wait()
}

以上代码有什么bug吗？