convert const std::shared_ptr<const T> into boost::shared_ptr<T>
You cannot transfer ownership from std::shared_ptr to boost::shared_ptr.
You might from a std::unique_ptr though.
But you can create a boost::shared_ptr with a custom deleter.
boost::shared_ptr<io_adaptor::msg::PandarScan>
msg_boost(const_cast<io_adaptor::msg::PandarScan*>(msg.get()),
[msg = msg](auto*) mutable { msg.reset(); });
Demo
Deleter captures original shared_ptr to maintain the lifetime,
and instead of releasing the resource, it just "decreases" the refcount.