@Test public void testJoin6() { Stamp dExactNonNull = StampFactory.exactNonNull(getType(D.class)); Stamp alwaysNull = StampFactory.alwaysNull(); Stamp join = join(alwaysNull, dExactNonNull); Assert.assertFalse(join.isLegal()); Assert.assertFalse(StampTool.isPointerNonNull(join)); Assert.assertFalse(StampTool.isPointerAlwaysNull(join)); }