Make OpFromGraph use prepare_node

theano/compile/builders.py

@@ -124,17 +124,14 @@ class OpFromGraph(gof.Op):
                          list(inputs) + self.shared_inputs,
                          [type() for type in self.output_types])
 
-    def make_thunk(self, node, storage_map, compute_map, no_recycling):
-        ret = super(OpFromGraph, self).make_thunk(node, storage_map,
-                                                  compute_map, no_recycling)
-        if not hasattr(self, "fn"):
-            self.fn = orig_function(self.new_inputs,
+    def prepare_node(self, node, storage_map, compute_map):
+        if not hasattr(node.tag, "fn"):
+            node.tag.fn = orig_function(self.new_inputs,
                                         self.new_outputs,
                                         **self.kwargs)
-        return ret
 
     def perform(self, node, inputs, outputs):
-        variables = self.fn(*inputs)
+        variables = node.tag.fn(*inputs)
         assert len(variables) == len(outputs)
         for output, variable in zip(outputs, variables):
             # TODO: when function's output-borrowing semantics are correct,