Const ref and rvalues again...

[jerro]

> The problem with binding rvalues to const ref is that you could 
> take and store the address of it. That's why I'd recommend 
> using "in ref" instead.

You can also take and store the address of a local variable that 
was passed as a const ref parameter, and accessing it after the 
caller exits will result in undefined behavior too. On the other 
hand,  addresses of both local variables and rvalues will be 
valid at least until the called function returns. Local variables 
and rvalues are equivalent in regard to this problem.