I recently stumbled upon this link: https://eigen.tuxfamily.org/dox/group__TopicPassingByValue.html
which (in short) says that passing Eigen objects by value is wrong. I'd like to get more info on that:
* When is this wrong? Is the object aligned when I create it but not when I make a copy of it on stack to pass it to a function? Could someone provide an example explaining what goes wrong?
* How is this avoided in case of returning by value?
* Does this affect custom-defined types of like Eigen::Matrix<2, -1, 0, 2, 3> (or Eigen::Matrix<2, 3, 0, 2, 3>) ?