num_dims = TF_GraphGetTensorNumDims(graph, feed_out_0, s);
  ASSERT_EQ(TF_OK, TF_GetCode(s)) << TF_Message(s);
  EXPECT_EQ(-1, num_dims);

  // Set the shape to be unknown, expect no change.
  TF_GraphSetTensorShape(graph, feed_out_0, /*dims=*/nullptr, -1, s);
  ASSERT_EQ(TF_OK, TF_GetCode(s)) << TF_Message(s);
  num_dims = TF_GraphGetTensorNumDims(graph, feed_out_0, s);