message: [TF RNN] Ensure dynamic_rnn runs at least one step to propagate dynamic shape info.
diff: @@ -812,7 +812,10 @@ def _dynamic_rnn_loop(cell,
  return (time + 1, output_ta_t, new_state)
  if in_graph_mode:
  - loop_bound = max_sequence_length
  + # Make sure that we run at least 1 step, if necessary, to ensure
  + # the TensorArrays pick up the dynamic shape.
  + loop_bound = math_ops.minimum(
  + time_steps, math_ops.maximum(1, max_sequence_length))
  else:
  # Using max_sequence_length isn't currently supported in the Eager branch.
  loop_bound = time_steps
  