D vs Java

[Dave]

In article <dvld6m$1f37$1 at digitaldaemon.com>, Sean Kelly says...
>
>similar semantics and C++ is far more heavily optimized.  If Java could 
>make one performance claim over C++ it would be that manipulating 
>references could be more efficient than passing copies, but D could make 
>the same claim... and can also take advantage of the optimizations that 
>contribute the performance of C++.
>

But C++ can also pass (and return) by reference if needed (obviating the need to
call copy ctors), correct? And it can allocate class objects on the stack, which
is an option Java doesn't have.

>Sean