add one assert in test_gpu_alloc_empty

theano/sandbox/cuda/tests/test_opt.py

@@ -160,7 +160,7 @@ def test_gpuallocempty():
                         mode=mode_with_gpu)
     l_gpu = f_gpu.maker.fgraph.toposort()
 
-    #assert numpy.any([isinstance(x.op, basic_ops.GpuAllocEmpty) for x in l_gpu])
+    assert numpy.any([isinstance(x.op, basic_ops.GpuAllocEmpty) for x in l_gpu])
     
     f_cpu = theano.function([], tensor.AllocEmpty('int32')(2,3),
                         mode=mode_with_gpu)