Cast return value of infer_shapes to int64 in ARange.infer_shape

theano/tensor/basic.py

@@ -3069,9 +3069,9 @@ class ARange(Op):
 
         if is_constant_value(step, 1):
             if is_constant_value(start, 0):
-                return [(stop,)]
+                return [(cast(stop, 'int64'),)]
             else:
-                return [((stop-start),)]
+                return [(cast(stop-start, 'int64'),)]
         else:
             return [(cast(ceil(cast((stop-start),'float64')/step),'int64'),)]