Re: [boost] Conflicts when building libraries at root

Subject: Re: [boost] Conflicts when building libraries at root
From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2015-03-10 04:08:02

On Tuesday 10 March 2015 06:54:30 Damien Buhl wrote:
> On 09/03/2015 23:20, Edward Diener wrote:
> > On 3/9/2015 5:09 PM, Andrey Semashev wrote:
> > [...]
> > 
> >> There weren't any warnings before. Is this a result of a change in
> >> Boost.PP?
> > 
> > Yes, but they were already in 1.57. The changes added some new
> > (BOOST_PP_IS_BEGIN_PARENS) and better functionality (the internal
> > BOOST_PP_IS_EMPTY) to Boost PP, as well as fixing some corner cases with
> > VC++ I discovered when testing VMD.
> 
> The reason why this happens more in this build, is that the new
> BOOST_FUSION_ADAPT macros uses BOOST_PP_IS_EMPTY for each field member
> now. This is used to determine if the type was provided or has to be
> deduced.

Is it possible to avoid BOOST_PP_IS_EMPTY? For example, use a keyword instead 
of testing for an empty string?

> > Turning off C4003 globally for VC++ is the only solution to the VC++
> > warnings I could ever discover. I attempted to turn off the warnings in
> > the macros where they occur, but VC++ just ignores that. Evidently the
> > warnings can only be turned off globally or possibly at the very
> > top-level macro which eventually causes them.
> 
> Do you think I could add specific pragmas to disable C4003 where I use
> BOOST_PP_IS_EMPTY ?

I suspect pragmas should envelop the place where the macro unfolds. In this 
case it's Boost.Phoenix. But in general this is user's code. And __pragma is 
not available in MSVC 8.