sisp

diff --git a/theano/tensor/basic.py b/theano/tensor/basic.py
index 8f734e2..52327a6 100644
--- a/theano/tensor/basic.py
+++ b/theano/tensor/basic.py
@@ -3804,6 +3804,202 @@ def vertical_stack(*args):
     return concatenate(args, axis=0)
 
 
+class FixUnknownDimension(Op):
+    """Infer an unknown dimension indicated by `-1`.

sisp

diff --git a/theano/tensor/nnet/nnet.py b/theano/tensor/nnet/nnet.py
index 788213d..e468385 100644
--- a/theano/tensor/nnet/nnet.py
+++ b/theano/tensor/nnet/nnet.py
@@ -1099,7 +1099,7 @@ class CrossentropySoftmax1HotWithBiasDx (gof.Op):
         return [g_dy, g_sm, g_y_idx]
 
     def c_code_cache_version(self):
-        return (3,)
+        return (4,)

sisp

class TemplateOp(theano.Op):
    @property
    def __impls__(self):
        return {}

    def __call__(self, *inputs, **kwargs):
        tag = kwargs.pop('tag', None)
        if tag is None:
            return super(TemplateOp, self).__call__(*inputs, **kwargs)

sisp

import theano
import theano.tensor as T
import numpy as np


def step(b, a, x, t, W):
    y = theano.dot(x[a:b], W)
    y = theano.printing.Print()(y)
    error = 0.5 * T.sqr(t[a:b] - y).sum()
    return b, error

sisp

import numpy as np
import theano
import theano.tensor as T


floatX = theano.config.floatX


def scan(y, dy_dw, w, x):
    def step(dy_dw_, y_, w_, a_, *x_):

sisp

import numpy as np
import theano
import theano.tensor as T


floatX = theano.config.floatX


def scan1(a, y, x=None):
    """

sisp

import numpy as np
import theano
import theano.tensor as T


floatX = theano.config.floatX


class GaussNewtonMatrix(object):
    def __init__(self, s):