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problem with passing subclass methods are parameters


Hi,

I'm having some difficulty in getting code that works great with version 
2.96 to work proprerly with version 3.0. I'm using g++ on  RedHat Linux 
with a 2.2 kernel.

Specifically, the compiler will no longer let me pass methods of a subclass 
of class A where a class A method is required. So, for a typedef FOO of the 
form

  typedef void (A::*FOO)(void);

where A is a class and B is a subclass of A, I can not pass methods of 
class B to functions requiring a parameter of type FOO.

More specifics below; the only options of note are -g2 and -W, and the 
exact compiler message is:

GsForwardThread.cpp:247: no matches converting function `handle_SMsg_Ping' to
    type `void (class LmThread::*)(class LmSrvMesgBuf*, class LmConnection*)'
GsForwardThread.h:50: candidates are: void
    GsForwardThread::handle_SMsg_Ping(LmSrvMesgBuf*, LmConnection*)

where the offensive line is

   REGISTER(SMsg::PING, (GsForwardThread::handle_SMsg_Ping));

and REGISTER is

#define REGISTER(mtype, handler)  RegisterHandler(mtype, 
(MsgHandler)&(handler))

and MsgHandler is

  typedef void (LmThread::*MsgHandler)(LmSrvMesgBuf* msgbuf, LmConnection* 
conn);

and GsForwardThread is a subclass of LmThread:

class GsForwardThread : public LmThread

Any thoughts on what to try to get this to compile? It seems every time I 
upgrade gcc, the method parameter passing breaks....

thanks so much!

Brent


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