p.nexty = head
		p.p = new(int)
		*p.p = 42
		head = p
		runtime.GC()
	}
	for p := head; p != nil; p = p.nexty {
		if *p.p != 42 {
			t.Fatal("corrupted heap")
		}
	}
}

func TestGcLastTime(t *testing.T) {
	ms := new(runtime.MemStats)
	t0 := time.Now().UnixNano()
	runtime.GC()
	t1 := time.Now().UnixNano()
	runtime.ReadMemStats(ms)
	last := int64(ms.LastGC)
	if t0 > last || last > t1 {