Hi, I just looked at the current state of variant and noticed that the implementation of recursive_variant's move ctor seems to be not as optimal as I hoped. The current implementation as written is: recursive_wrapper<T>::recursive_wrapper(recursive_wrapper&& operand) : p_(new T( detail::variant::move(operand.get()) )) { } Unless I am mistaken, I think the heap allocation is not needed and the target should simply grab the pointer and mark the source pointer as 0 (with additional checks for 0 in the dtor): template <typename T> recursive_wrapper<T>::recursive_wrapper(recursive_wrapper&& operand) : p_(operand.release()) { } template <typename T> T* recursive_wrapper<T>::release() { T* ptr = p_; p_ = 0; return ptr; } template <typename T> recursive_wrapper<T>::~recursive_wrapper() { if (p_) boost::checked_delete(p_); } The tests are running just fine (tested with gcc, msvc) with this (more optimal) implementation. I also run the Spirit test suite (Spirit makes heavy use of variant). Thoughts? I can commit this patch if it is acceptable. Regards, -- Joel de Guzman http://www.boostpro.com http://boost-spirit.com