GPU doesn't support -1 reshaping

theano/tensor/basic.py

@@ -7208,14 +7208,18 @@ def tensordot(a, b, axes = 2):
         outshape = concatenate([a.shape[:a.ndim - axes], b.shape[axes:]])
         outndim = a.ndim + b.ndim - (2 * axes)
 
-        a_shape_0 = b_shape_0 = 1
+        a_shape_0 = b_shape_0 = a_shape_1 = b_shape_1 = 1
         for s0 in range(a.ndim - axes):
             a_shape_0 *= a.shape[s0]
         for s0 in range(axes):
             b_shape_0 *= b.shape[s0]
+        for s1 in range(a.ndim - axes, a.ndim):
+            a_shape_1 *= a.shape[s1]
+        for s1 in range(axes, b.ndim):
+            b_shape_1 *= b.shape[s1]
 
-        a_reshaped = a.reshape((a_shape_0, -1), ndim = 2)
-        b_reshaped = b.reshape((b_shape_0, -1), ndim = 2)
+        a_reshaped = a.reshape((a_shape_0, a_shape_1), ndim = 2)
+        b_reshaped = b.reshape((b_shape_0, b_shape_1), ndim = 2)
 
         return _dot(a_reshaped, b_reshaped).reshape(outshape, outndim)