[boost] Re: Copying (Was: Empty Base Optimization)

From: Valentin Bonnard (Bonnard.V_at_[hidden])
Date: 1999-11-21 04:54:06

Greg Colvin wrote:

> That is, given an inlined constructor
> 
>   struct X { T t; X(T t):t(t){} };
> 
> is the compiler required to make a copy of the T parameter, or can it assign
> the T argument directly to the T member?  That is, in the statement
> 
>    X x(t);
> 
> is the compiler allowed to copy t only once, or must it first push it on
> the stack?

The compiler must copy t twice. t, t and t must be three different 
objects.

-- 
Valentin Bonnard