// Get non existent attribute
  TF_Buffer* attr_buf = TF_NewBuffer();
  TF_FunctionGetAttrValueProto(func_, "foo_attr", attr_buf, s_);
  EXPECT_EQ(TF_INVALID_ARGUMENT, TF_GetCode(s_));
  EXPECT_EQ(string("Function 'MyFunc' has no attr named 'foo_attr'."),
            string(TF_Message(s_)));
  TF_DeleteBuffer(attr_buf);

  // Set attr
  tensorflow::AttrValue attr;