GCC 4.5.2 Linker gots Problem while using Exceptions (C++) - c++

Question

I try to write a webserver. As far as I am, it works quiet good with Windows. But I want to make it also Unix compatible. And I think there has to be a problem with the heredity f the exception class.
For better understanding, just the important parts:
server.cpp
#include <exception>
#include <stdexcept>
#ifdef __unix__
#include "UnixSocket.h"
#elif __WIN32__ || _MSC_VER
#include "WinSocket.h"
#endif
#include "HTTPParser.h"
int main(void) {
try {
socket->socketInit(PORT);
}
catch (exception &e) {
cout << endl << "Exception: " << e.what() << endl;
socket->cleanAll();
}
return 0
}
NetInterface.h
class NetInterface : public exception {
private:
public:
virtual void socketInit(const char *port) = 0;
virtual void cleanAll(void) = 0;
virtual void cleanPersCon(void) = 0;
virtual char *akzeptieren(void) = 0;
virtual void empfangen(void) = 0;
virtual void senden(void) = 0;
virtual void *get_in_addr(struct sockaddr *sa) = 0;
virtual string getIncoming(void) = 0;
virtual void setOutcoming(string s) = 0;
virtual ~NetInterface() throw() {};
};
UnixSocket.h
class UnixSocket : virtual public NetInterface {
private:
[...]
public:
UnixSocket(void);
//kill socket connections
void cleanAll(void);
void cleanPersCon(void);
//SysCalls
void socketInit(const char *port);
char *akzeptieren(void);
void empfangen(void);
void senden(void);
//Getter and Setter
string getIncoming(void);
void setOutcoming(string s);
virtual ~UnixSocket() throw() {};
};
HTTPParser.h
class HTTPParser : public exception {
private:
[...]
public:
HTTPParser(NetInterface *_socket, string _path);
void parsePacket(void);
virtual ~HTTPParser() throw() {};
};
There you can se a short summary of the class declarations.
But now the gcc tells me something like this:
/tmp/cc8DNmKI.o:(.rodata._ZTV10HTTPParser[vtable for HTTPParser]+0x10): undefined reference to `std::exception::what() const'
/tmp/cc8DNmKI.o:(.rodata._ZTV10UnixSocket[vtable for UnixSocket]+0x14): undefined reference to `std::exception::what() const'
/tmp/cc8DNmKI.o:(.rodata._ZTV10UnixSocket[vtable for UnixSocket]+0x78): undefined reference to `std::exception::what() const'
/tmp/cc8DNmKI.o:(.rodata._ZTV12NetInterface[vtable for NetInterface]+0x10): undefined reference to `std::exception::what() const'
/tmp/cc8DNmKI.o:(.rodata._ZTV12NetInterface[vtable for NetInterface]+0x14): undefined reference to `__cxa_pure_virtual'
/tmp/cc8DNmKI.o:(.rodata._ZTV12NetInterface[vtable for NetInterface]+0x18): undefined reference to `__cxa_pure_virtual'
/tmp/cc8DNmKI.o:(.rodata._ZTV12NetInterface[vtable for NetInterface]+0x1c): undefined reference to `__cxa_pure_virtual'
/tmp/cc8DNmKI.o:(.rodata._ZTV12NetInterface[vtable for NetInterface]+0x20): undefined reference to `__cxa_pure_virtual'
/tmp/cc8DNmKI.o:(.rodata._ZTV12NetInterface[vtable for NetInterface]+0x24): undefined reference to `__cxa_pure_virtual'
/tmp/cc8DNmKI.o:(.rodata._ZTV12NetInterface[vtable for NetInterface]+0x28): more undefined references to `__cxa_pure_virtual' follow
/tmp/cc8DNmKI.o:(.rodata._ZTVSt16invalid_argument[vtable for std::invalid_argument]+0x10): undefined reference to `std::logic_error::what() const'
/tmp/cc8DNmKI.o:(.rodata._ZTVSt12domain_error[vtable for std::domain_error]+0x10): undefined reference to `std::logic_error::what() const'
/tmp/cc8DNmKI.o:(.rodata._ZTI10HTTPParser[typeinfo for HTTPParser]+0x0): undefined reference to `vtable for __cxxabiv1::__si_class_type_info'
/tmp/cc8DNmKI.o:(.rodata._ZTI10HTTPParser[typeinfo for HTTPParser]+0x8): undefined reference to `typeinfo for std::exception'
/tmp/cc8DNmKI.o:(.rodata._ZTI10UnixSocket[typeinfo for UnixSocket]+0x0): undefined reference to `vtable for __cxxabiv1::__vmi_class_type_info'
/tmp/cc8DNmKI.o:(.rodata._ZTI10UnixSocket[typeinfo for UnixSocket]+0x18): undefined reference to `typeinfo for std::exception'
/tmp/cc8DNmKI.o:(.rodata._ZTI12NetInterface[typeinfo for NetInterface]+0x0): undefined reference to `vtable for __cxxabiv1::__si_class_type_info'
/tmp/cc8DNmKI.o:(.rodata._ZTI12NetInterface[typeinfo for NetInterface]+0x8): undefined reference to `typeinfo for std::exception'
/tmp/cc8DNmKI.o:(.rodata._ZTISt16invalid_argument[typeinfo for std::invalid_argument]+0x0): undefined reference to `vtable for __cxxabiv1::__si_class_type_info'
/tmp/cc8DNmKI.o:(.rodata._ZTISt16invalid_argument[typeinfo for std::invalid_argument]+0x8): undefined reference to `typeinfo for std::logic_error'
/tmp/cc8DNmKI.o:(.rodata._ZTISt12domain_error[typeinfo for std::domain_error]+0x0): undefined reference to `vtable for __cxxabiv1::__si_class_type_info'
/tmp/cc8DNmKI.o:(.rodata._ZTISt12domain_error[typeinfo for std::domain_error]+0x8): undefined reference to `typeinfo for std::logic_error'
/tmp/cc8DNmKI.o:(.eh_frame+0xeb): undefined reference to `__gxx_personality_v0'
collect2: ld returned 1 exit status
and even more....

Answer 1

Judging from undefined reference to __gxx_personality_v0 linker message it looks like you are linking with gcc. You need to link C++ applications with g++. Or link with gcc and add -lstdc++ to the linker command line.

Answer 2

You aren't showing the relevant code and compiler invocation, but know that std::exception has an unimplemented virtual member function what() that you're expected to override, so don't go throwing naked std::exceptions if you want to callwhat().
Any of the derived, specific exceptions in <stdexcept> will implement what() and allow you to store a message when you're constructing the exception object.