}
	if n != 0 {
		t.Errorf("ReadFromUDP got n %d want 0", n)
	}
	if addr != nil {
		t.Errorf("ReadFromUDP got addr %+#v want nil", addr)
	}
}

func TestAllocs(t *testing.T) {
	switch runtime.GOOS {
	case "plan9", "js", "wasip1":
		// These implementations have not been optimized.
		t.Skipf("skipping on %v", runtime.GOOS)
	}
	if !testableNetwork("udp4") {

	check(o2, "o2", "c1k1", "o2k2", "")

	o3 := otherContext{c4}
	check(o3, "o3", "", "c2k2", "c3k3")

	o4 := WithValue(o3, k3, nil)
	check(o4, "o4", "", "c2k2", "")
}

func TestAllocs(t *testing.T) {
	bg := Background()
	for _, test := range []struct {
		desc       string
		f          func()
		limit      float64
		gccgoLimit float64
	}{
		{
			desc:       "Background()",