ReservedSpace::ReservedSpace(size_t size, size_t alignment,
                             bool large,
                             char* requested_address,
                             const size_t noaccess_prefix) {

  {- -------------------------------------------
  (1) ReservedSpace::initialize() を呼んで初期化を行う.
      ---------------------------------------- -}

      initialize(size+noaccess_prefix, alignment, large, requested_address,
                 noaccess_prefix, false);
    }