From what I've googled, it seems like symbol reference errors are linking errors.. If I am wrong, please let me know.

I'm trying to make a very simple program(DataReader.cpp) that takes inputs from a text file and saves them in a form specified in Data.cpp/Data.h. But I keep getting symbol reference errors

g++ -Wall DataReader.o Data.o -o DataReader
Undefined                       first referenced
 symbol                             in file
Data::Data(char, char, char, char, char, char, char, char, char, bool)DataReader.o
ld: fatal: Symbol referencing errors. No output written to DataReader

What can I do to resolve this issue? I've been working at it for a while now but I have not a single clue. Again, it's a real simple program that includes vector, iostream and fstream. So I presume that there's no need for me to link libraries or anything, do I? I've used those before and didn't have to link it explicitly.

Thank you!!

this is my makefile..

all: DataReader

DataReader.o: DataReader.cpp
	g++ -Wall -c DataReader.cpp -o DataReader.o
Data.o: Data.cpp
	g++ -Wall -c Data.cpp -o Data.o

DataReader: DataReader.o Data.o
	g++ -Wall DataReader.o Data.o -o DataReader
class Data

	char UL;					// Upper Left Corner of the board
	char UM;					// Upper Middle
	char UR;					// Upper Right
	char ML;					// Middle Left
	char MM;					// Middle Middle
	char MR;					// Middle Right
	char BL;					// Bottom Left
	char BM;					// Bottom Middle
	char BR;					// Bottom Right
	bool result;				// Classification Result

	Data();			// default constructor
	Data(	char _UL, char _UM, char _UR,
			char _ML, char _MM, char _MR,
			char _BL, char _BM, char _BR, bool _result );

	void setData(char _UL, char _UM, char _UR,
				char _ML, char _MM, char _MR,
				char _BL, char _BM, char _BR, bool _result );
	char getUL();
	char getUM();
	char getUR();
	char getML();
	char getMM();
	char getMR();
	char getBL();
	char getBM();
	char getBR();
	bool getResult();
#include "Data.h"

void Data::setData(char _UL, char _UM, char _UR,
					char _ML, char _MM, char _MR,
					char _BL, char _BM, char _BR, bool _result)
	UL = _UL;
	UM = _UM,
	UR = _UR;
	ML = _ML;
	MM = _MM;
	MR = _MR;
	BL = _BL;
	BM = _BM;
	BR = _BR;
	result = _result;

char Data::getUL()	{	return UL;	}
char Data::getUM()	{	return UM;	}
char Data::getUR()	{	return UR;	}
char Data::getML()	{	return ML;	}
char Data::getMM()	{	return MM;	}
char Data::getMR()	{	return MR;	}
char Data::getBL()	{	return BL;	}
char Data::getBM()	{	return BM;	}
char Data::getBR()	{	return BR;	}
bool Data::getResult() {	return result;	}
#include <fstream>
#include <iostream>
#include <vector>
#include "Data.h"

using namespace std;

int main()
	ifstream boardComboText;
	char att;
	char buffer[28];
	Data * something = new Data('x','x','x','x','x','x','x','x','x',1);
	att = (*something).getML();
	cout << "something " << att;
	vector<Data> database;"tic-tac-toe-training.txt");
		cerr << "file can't be opened";
	while(! boardComboText.eof())
		bool result;
		if(buffer[18] == 'p')
			result = 1;
			result = 0;
		Data temp = new Data(buffer[0], buffer[2], buffer[4],
								buffer[6], buffer[8], buffer[10],
								buffer[12], bufffer[14], buffer[16], result);
	return 0;

Much thanks to anyone who read this mess of a code...

Recommended Answers

All 2 Replies

No body of Data constructor, only the declaration.

commented: Thank you very much!!! +1

No body of Data constructor, only the declaration.


wow.. that did fix the problem alright. THANK YOU VERY MUCH!!!!

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