[Patch/RFC] Implement the resolution of DR 409 [Ready]

[Benjamin Kosnik]

> this is a rather welcome resolution, in my opinion, answering one of the 
> most frequently reported not-a-bug. The patch is straightforward, and should not
> break most sensible user code, but I propose to have it also for 4.0 (i.e.,
> not only mainline), since a non-trivial change of behavior seems more suited
> for a major release.

Thanks for doing this Paolo. I agree, this is a very welcome bug fix.

-benjamin