Merge pull request #3323 from SinaHonari/issue3031

theano/tensor/basic.py

@@ -4126,7 +4126,11 @@ class Reshape(Op):
         x = as_tensor_variable(x)
         shp_orig = shp
         shp = as_tensor_variable(shp, ndim=1)
-        if not shp.dtype.startswith('int'):
+        if not (shp.dtype.startswith('int') or
+                (isinstance(shp, TensorConstant) and shp.data.size == 0)):
+            # It raises an error if shp is not of integer type,
+            # except when shp is constant and empty
+            # (in this case, shp.dtype does not matter anymore).
             raise TypeError("Shape must be integers", shp, shp.dtype)
         assert shp.ndim == 1
         if isinstance(shp, TensorConstant):

theano/tensor/tests/test_basic.py

@@ -5052,6 +5052,11 @@ class T_reshape(utt.InferShapeTester, utt.TestOptimizationMixin):
         f = self.function([x], x.reshape((0, 100)))
         assert f(numpy.ndarray((0,), dtype='float32')).shape == (0, 100)
 
+    def test_empty_shp(self):
+        const = theano.tensor.constant([1]).reshape(())
+        f = function([], const)
+        assert f().shape == ()
+
 
 def test_make_column_matrix_broadcastable():
     # The goal of the operation made by `b` is to ensure the second dimension