Fails with "invalid UTF-8 on line 1"

googlealertsfail.go

package main

import (
	"bytes"
	"log"
	"net/http"
	"strings"

	"launchpad.net/xmlpath"
)

func main() {
	// retrieve Google Alerts feed for "go"
	resp, _ := http.Get("https://www.google.com/alerts/feeds/05850118961943884337/16879813453666049819")
	buf := &bytes.Buffer{}
	buf.ReadFrom(resp.Body)
	s := buf.String()

	t, err := xmlpath.Parse(strings.NewReader(s))
	if err != nil {
		log.Fatal("Failed.", err, t)
	}
}

withoutxmlpath.go

package main

import (
	"bytes"
	"encoding/xml"
	"fmt"
	"net/http"
	"strings"
	"unicode/ut8"
)

func main() {
	resp, _ := http.Get("https://www.google.com/alerts/feeds/05850118961943884337/16879813453666049819")
	buf := &bytes.Buffer{}
	buf.ReadFrom(resp.Body)
	s := buf.String()
	fmt.Println(utf8.ValidString(s))

	d := xml.NewDecoder(strings.NewReader(s))
	for {
		t, err := d.Token()
		fmt.Printf("%T\n", t)
		if err != nil {
			fmt.Println(err)
			break
		}
	}
}