Give a deterministic name to composite ops

theano/scalar/basic.py

@@ -1961,12 +1961,13 @@ class Composite(ScalarOp):
 
         if not hasattr(self,"name"):
             l=[]
-            for n in env.nodes:
+            for n in env.toposort():
                 if hasattr(n.op,"name") and n.op.name is not None:
                     v=n.op.name
                     if v.startswith("Composite"):
                         v = v[len("Composite"):]
-                else: v=n.op.__class__.__name__
+                else:
+                    v=n.op.__class__.__name__
                 l.append(v)
             self.name="Composite{"+",".join(l)+"}"