The ArrayHandle classes all exclusively work in the control environment.
However, CUDA likes to add __device__ to constructors, destructors, and
assignment operators it automatically adds. This in turn causes warnings
about the __device__ function using host-only classes (like
boost::shared_ptr). Solve this problem by adding explicit methods for
all of these.
Implemented this by wrapping up all these default objects in a macro.
This also solved the problem of other constructors that are necessary
for array handles such as a constructor that takes the base array
handle.
Under CUDA, the default constructors and destructors created are exported
as __host__ and __device__, which causes problems because they used a boost
pointer that only works on the host. The explicit copy constructors and
destructors do the same thing as the default ones except declared to only
work on the host.