Re: dynamic_cast problem

[Rolf Magnus]

Ulrich Eckhardt wrote:

> KeithO wrote:
>> extern "C" DestinationImpl * getDestinationImpl(void);
> 
>>     MODULE_HANDLE fn = (void *(*)())dlsym(hdll,
>>     "getDestinationImpl");
> 
> The functiontypes don't match. Further, I'd use a typedef(at least for
> your readers).

He does use a typedef, but for some reason, he doesn't use it for the
cast, but only for defining fn.

> Also consider that this cast is not valid, neither in C 
> nor C++. Take a look at comp.lang.c++.moderated, there was a thread
> started by me that explains the details.

I don't think you can use a valid cast in this place at all. That's just
a problem with dlsym.

> BTW: why pass around a void*? Your lib could as well declare the
> struct class and export a function returning a pointer to it.

That's what the lib is actually doing. The OP is just interpreting that
pointer as a void* in the main program and then converting that "back"
into a DestinationImpl*.