Question

I’m getting this error creating a new object with KarateMatch new_match; when compiling my Driver.cpp file with g++ Driver.cpp KarateMatch.cpp -o output:

Undefined symbols for architecture x86_64:
"KarateMatch::KarateMatch()", referenced from:
  _main in cc5G5Ak8.o
ld: symbol(s) not found for architecture x86_64
 collect2: ld returned 1 exit status

KarateMatch new_match;

I can’t figure out what I’ve done wrong, since I am using #include <KarateMatch.h> on both Driver.cpp and KarateMatch.cpp:

Edit:

I’ve tried the code as exactly shown on my system (OS X 10.8.1), and this isn’t compiling with the same error.

KarateMatch.h

#include <iostream>
#include <string>
#include <vector>

using namespace std;

class KarateMatch{

    public:
        KarateMatch();
};

KarateMatch.cpp

#include "KarateMatch.h"
#include <iostream>
#include <string>
#include <vector>

using namespace std;

KarateMatch::KarateMatch(){
    cout << "HI";
}

Answer 1

its running fine on my system g++-4.3..
i think its not the problem with KarateMatch.h and KarateMatch.cpp files.

try compiling only Driver.cpp first without including KarateMatch.h file and without creating its object .