x, y := read2(b)
			if x&0xff00 != y&0xff00 {
				t.Errorf("x=%x y=%x\n", x, y)
				done <- false
				return
			}
		}
		done <- true
	}()
	<-done
	<-done
}

func TestDupLoad(t *testing.T) {
	main1(t)
	main2(t)