Re: [Boost-Users] Re: Re: boost::signals build and C++Builder 6 Pro in 1.29.0

From: Beman Dawes (bdawes_at_[hidden])
Date: 2003-03-05 16:34:33

At 10:58 PM 3/4/2003, Douglas Gregor wrote:

 >On Tuesday 04 March 2003 10:16 pm, Edward Diener wrote:
 >> Beman Dawes wrote:
 >> > Have you considered proposing a macro which will automatically apply
 >> > the appropriate #pragma for the compiler? That way the knowledge of
 >> > what #pragma to apply for each compiler only has to be maintained and
 >> > tested in one place.
 >>
 >> Excellent idea. Now why didn't I think of that <g>. It's the old forest 

 >> and the trees thing, no doubt.
 >>
 >> The macro would have to be in the form of:
 >>
 >> BOOST_DATA_LAYOUT_BEGIN
 >>
 >> at the beginning of a header file surrounding any 
class/struct/union/enum
 >> declarations and
 >>
 >> BOOST_DATA_LAYOUT_END
 >>
 >> at the end.
 >
 >Would you willing to provide the definitions for these macros (or, as I
 >suspect, begin/end headers)? I'd be happy to use them, but as I've never
 >needed such a thing I don't know the particular pragmas to use.

I'm in the same boat as Doug, and I expect other Boost developers are too.

It isn't just a header (and docs) that are needed; test cases would be 
important too. It would be easy for mistakes in these macros to give the 
appearance of working, but actually do nothing. If I understand it, you can 
only tell they are working correctly with a fairly sophisticated build test 
that deliberately tries to use object files compiled with conflicting 
options.

--Beman