On Sat, 13 Mar 2010 14:33:12 -0500 Christian Henning <chhenning@gmail.com> wrote:
Hi Mateusz,
On Sat, Mar 13, 2010 at 1:23 PM, Mateusz Loskot <mateusz@loskot.net> wrote:
Christian Henning wrote:
2) I notice you saying that you're getting linker errors - that should only happen if you're taking the address of the constants somewhere - if that's a use case that you want to support, then you need a definition for the constants somewhere - suitably guarded by the right Boost.Config macros (sorry can't remember what off the top of my head).
I'm getting a compiler error with gcc 3.4.5. The compiler that comes with MinGW.
Is it compiler error or linker error?
I don't remember off the top of my head. It might have been a linker error, though. Don't have access right now to gcc.
This can be fixed, inconveniently, by adding external definition:
struct pnm_image_type : property_base<int> { typedef pnm_image_type self_type; BOOST_STATIC_CONSTANT( type, _mono_asc = 1 ); }; const int pnm_image_type::_mono_asc;
Wouldn't that create multiple instances when including this header file more than one time?
If declared extern you ought to be fine. extern const int pnm_image_type::_mono_asc; Cheers, -- Manfred