Ignore new trees. This isn't needed as we don't add new node anyway

theano/tensor/opt.py

@@ -5516,7 +5516,7 @@ def constant_folding(node):
     return rval
 
 
-topo_constant_folding = in2out(constant_folding, ignore_newtrees=False,
+topo_constant_folding = in2out(constant_folding, ignore_newtrees=True,
                                name="topo_constant_folding")
 register_canonicalize(topo_constant_folding, 'fast_compile', final_opt=True)
 register_stabilize(topo_constant_folding, 'fast_compile', final_opt=True)