如何解决go中的分段冲突?

我正在go中编写一个spider,到目前为止,我有以下代码:

import (
    "fmt"
    "math/rand"
    "net/http"
    "runtime"
    "time"

    "golang.org/x/net/html"
)

func handleEnd() {
    //handle end (close channels, etc)
    fmt.Println("Placeholder")
}

func worker(c chan string) {
    var url string
    url = <-c
    fmt.Println(url)
    //get the url
    resp, err := http.Get(url)
    defer resp.Body.Close()
    if err != nil {
        fmt.Println(err)
        //we should log this incase this is in the background
    }

    //operate on it
    //find links
    z := html.NewTokenizer(resp.Body)
    for {
        tt := z.Next()

        switch {
        case tt == html.ErrorToken:
            // End of the document, we're done
            return
        case tt == html.StartTagToken:
            t := z.Token()

            isAnchor := t.Data == "a"
            if isAnchor {
                fmt.Println("We found a link!")
            }
        }
    }
    //handle local links()
    //send links to channel
    //}
}

func genStartUrls(howMany, length int) []string {
    var ans []string
    var letters = []rune("abcdefghijklmnopqrstuvwxyz")
    rand.Seed(time.Now().UnixNano())
    for i := 0; i < howMany; i++ {
        b := make([]byte, length)
        for i := range b {
            b[i] = byte(letters[rand.Intn(len(letters))])
        }
        ans = append(ans, "http://"+string(b)+".com")
    }
    return ans
}

func main() {
    defer handleEnd()
    workers := 3
    l := make(chan string, 10000)
    defer close(l)
    for _, url := range genStartUrls(100, 3) {
        l <- url
    }
    for i := 0; i < workers; i++ {
        go worker(l)
    }
    for {
        runtime.Gosched()
    }
}

起初,它按预期工作(它从页面中找到了HREF),但当我打破它并再次运行它,然后再做几次同样的事情时,我得到了以下错误:

[signal SIGSEGV: segmentation violation code=0x1 addr=0x40 pc=0x6454f1]

goroutine 7 [running]:
main.worker(0xc0000662a0)
        /home/name/go/src/spider/main.go:25 +0x121
created by main.main
        /home/name/go/src/spider/main.go:85 +0x138
exit status 2

当我重新启动电脑时,这个问题在程序运行几次后就消失了,但随后又回来了。这让我觉得goroutines可能不会在我的主程序结束时结束,而是继续作为僵尸进程。如何修复此错误?