dont check value for None eval point

theano/tensor/basic.py

@@ -4580,12 +4580,14 @@ class Dot(Op):
                     'second input passed to Dot.R_op has no test value')
                 debugger_available = False
 
+            if eval_points[0]:
                 try:
                     ev0 = gof.op.get_test_value(eval_points[0])
                 except AttributeError:
                     gof.op.missing_test_message(
                         'first eval point passed to Dot.R_op has no test value')
                     debugger_available = False
+            if eval_points[1]:
                 try:
                     ev1 = gof.op.get_test_value(eval_points[1])
                 except AttributeError:
@@ -4598,7 +4600,8 @@ class Dot(Op):
             eval_point_values = [ev0, ev1]
 
             for i in xrange(2):
-                if input_values[i].shape != eval_point_values[i].shape:
+                if eval_pooint_values[i] and \
+                   input_values[i].shape != eval_point_values[i].shape:
                     raise ValueError('input ' + str(i) + ' and eval_point ' +
                                      str(i) + ' to Dot.R_op '
                                      'should have the '