Remove the restriction on zero target dimensions when reshaping a CudaNdarray

theano/sandbox/cuda/cuda_ndarray.cu

@@ -871,8 +871,8 @@ PyObject * CudaNdarray_Reshape(CudaNdarray * self, PyObject * shape)
                 free(rval_dims);
                 return NULL;
             }
-            if(rval_dims[i]<=0){
-                PyErr_Format(PyExc_ValueError, "Reshape has invalid dimension %i (must be >0)",rval_dims[i]);
+            if(rval_dims[i]<0){
+                PyErr_Format(PyExc_ValueError, "Reshape has invalid dimension %i (must be >=0)",rval_dims[i]);
                 free(rval_dims);
                 return NULL;
             }

theano/sandbox/cuda/tests/test_basic_ops.py

@@ -374,6 +374,11 @@ def test_reshape():
     except ValueError:
         pass
 
+    # Test zero dimensions are allowed
+    x = T.vector('x')
+    f_reshp = theano.function([x], x.reshape((0,100)), mode=mode_with_gpu)
+    assert f_reshp(numpy.ndarray((0,), dtype='float32')).shape == (0,100)
+
 
 def test_alloc_empty():
     # Test that we allocated correctly