[PATCH] Exploit move semantics in std::accumulate.

[Marc Glisse]

On Tue, 11 Jan 2011, Christopher Jefferson wrote:

> It is my belief that indeed we can't be sure that x=move(x) will behave 
> correctly.
>
> However, doing x = f(move(x), y) should be fine. Unless of course f just 
> returns an rvalue reference to it's first argument. But then f is a very 
> badly behaved function, possibly with other issues.

Hmm, I believe the issue can happen even if f returns an object (not a 
reference). Indeed that object may still "be x", either because it was 
move-initialized from x, or because of copy elision (yes I know compilers 
don't usually perform the elision here).

(we might want to move the discussion to csc++ or some such place)

-- 
Marc Glisse