if (input_shape.has_value()) {
        TF_ShapeAndTypeListSetShape(input_shapes, i, input_shape->data(),
                                    input_shape->size());
      } else {
        TF_ShapeAndTypeListSetUnknownShape(input_shapes, i);
      }
    }
    TF_ShapeAndTypeList* output_shapes;
    TFE_InferShapes(op, input_shapes,
                    input_tensors.empty()
                        ? nullptr

    int num_shapes);
TF_CAPI_EXPORT extern void TF_ShapeAndTypeListSetShape(
    TF_ShapeAndTypeList* shape_list, int index, const int64_t* dims,
    int num_dims);
TF_CAPI_EXPORT extern void TF_ShapeAndTypeListSetUnknownShape(
    TF_ShapeAndTypeList* shape_list, int index);
TF_CAPI_EXPORT extern void TF_ShapeAndTypeListSetDtype(
    TF_ShapeAndTypeList* shape_list, int index, TF_DataType dtype);

  DCHECK(num_dims >= 0) << "Number of dimensions cannot be negative!";
  shape.num_dims = num_dims;
  shape.dims = new int64_t[num_dims];
  memcpy(shape.dims, dims, sizeof(int64_t) * num_dims);
}

void TF_ShapeAndTypeListSetUnknownShape(TF_ShapeAndTypeList* shape_list,
                                        int index) {
  DCHECK(index >= 0 && index < shape_list->num_items);
  TF_ShapeAndType& shape = shape_list->items[index];