Intel Xeon Phi offload code + STL vector

i would like to copy data stored in STL vector to Intel Xeon Phi coprocessor. In my code, I created class which contains vector with data needed to computation. I want to create class object on host, initialize data on host too and then I want to send this object to coprocessor. This is simple code which illustrate what i want to do. After copy object to the coprocessor vector is empty. What can be problem? How do it correctly?i would like to copy data stored in STL vector