Re: [orbitcpp-list] question about ORBit-tools

[Phil D. <ph...@us...>]

Ronald Garcia wrote:
> 
> hey guys,
>      got a question about some code I found in orbitcpp_tools.hh.
> 
> There is some code which goes like so:
> 
> #ifdef ORBITCPP_HAVE_BAD_CAST
>         #define ORBITCPP_NARROW_OR_NULL(type,item) \
>                 type *result; \
>                 try { \
>                         result = dynamic_cast<type *>(item); \
>                 } \
>                 catch (bad_cast) {\
>                     result = NULL; \
>                 }
> #else
>         #warning ORBit-C++ will not detect narrowing errors on pseudo objects.
>         #define ORBITCPP_NARROW_OR_NULL(type,item) \
>                 type *result = static_cast<type *>(item);
> #endif
> 
> a few questions/comments:
> 
>      1)  In C++, dynamic casting to a pointer type doesn't throw
> exceptions, it just returns a 1.  bad_cast is thrown on dynamic casts
> to references...ie, I don't think that code will work.
> 

I don't think the dynamic cast thing will work at all, since it requires
rtti information AFAIK, and we're using reinterpret_casted C objects
which won't have this information (since no vtable etc..). Andreas?

Cheers,

Phil.