Re: [boost] [config] Variadic template macros in gcc header

Subject: Re: [boost] [config] Variadic template macros in gcc header
From: Peter Dimov (pdimov_at_[hidden])
Date: 2010-11-24 09:00:49

Edward Diener wrote:
> On 11/22/2010 2:40 PM, Daniel James wrote:
> > On 22 November 2010 14:33, Edward Diener<eldiener_at_[hidden]> 
> > wrote:
> >>
> >> Is this also the intention of Boost in general, that an empty config.h 
> >> means
> >> a compiler that supports C++03 ?
> >
> > In general, an empty config.hpp means C++0x. That did seem to be the
> > consensus decision, and I think everyone went into it understanding
> > the consequences. It looks like the decision was made here (only the
> > first few replies are relevant):
> >
> > http://thread.gmane.org/gmane.comp.lib.boost.devel/175638
>
> In that case Peter Dimov's assumption seems wrong. He is saying that he 
> did not want you to make the changes because an empty config.h should mean 
> the C++ standard, aka C++03.

No, I'm not saying that it _should_ mean C++03, I'm saying that it does mean 
C++03, and has meant C++03 for years. A previously valid (but admittedly 
rare) use case - using shared_ptr with an empty config.hpp - will be 
rendered invalid. This is not an assumption, it is a fact.

It will be OK to make the change when most compilers we care about are 
reasonably C++0x compliant in their default mode, but this is not the case 
today.