Getting a Dwarf Error Version '4'

Question

I am having some trouble with my school project. I think that it may be an error with my use of pointers but I am not sure why I am getting this error. This code is incomplete but I am trying to test it along the way. Do you have any idea why I am getting this error and what does it mean? Thanks!

Error from Cygwin Terminal

-bash-3.2$ make clean
rm -rf *.o simulate
-bash-3.2$ make simulate
g++ -c -g Main.cpp
g++ -c -g Maze.cpp
g++ Main.o Maze.o -o simulate
/usr/bin/ld: Dwarf Error: found dwarf version '4', this reader only handles version 2 information.
Maze.o: In function `Maze::createMaze(char*)':
Maze.cpp:(.text+0x49): undefined reference to `Node::Node(char)'
collect2: error: ld returned 1 exit status
make: *** [simulate] Error 1

Main.cpp

#include <iostream>
#include <fstream>
#include <string>
#include "Maze.h"
using namespace std;

int main()
{
    int array_size = 1024;
    char * mazeArray = new char[array_size];
    int position = 0;
    string mazeName;
    Maze Maze1;

    cout << "Enter the name of the maze file: ";
    getline(cin, mazeName);

    ifstream fin(mazeName.c_str());
    //File opened successfully
    if(fin.is_open())
    {
        while(!fin.eof() && position < array_size)
        {
            fin.get(mazeArray[position]); //reading one character from file to mazeArray
            position++;
        }
        mazeArray[position-1] = '\0'; //placing character mazeArray terminating character

        for(int i = 0; mazeArray[i] != '\0'; i++){
            if(isspace(mazeArray[i]))
                mazeArray[i] = mazeArray[i+1];
        }

        cout << "Displaying mazeArray..." << endl << endl;
        //this loop display all the charaters in mazeArray till \0 
        for(int i = 0; mazeArray[i] != '\0'; i++)
        {
            cout << mazeArray[i];
        }
        cout << endl;

        Maze1.createMaze(mazeArray);

    }
    else //file could not be opened
    {
        cout << "File could not be opened." << endl;
    }

    return 0;
}

Maze.h

#ifndef MAZE_H
#define MAZE_H
#include <string>
#include <sstream>
#include <vector>

#include "Node.h"
using namespace std;

class Maze
{
        public:
            void createMaze(char*);
            void availablePaths();
            void displayPath();
            void moveNorth();
            void moveSouth();
            void moveEast();
            void moveWest();
            int getroomCount();
            char getpathHistory();
            char getcurrentRoom();

        private:
            int roomCount;
            char pathHistory[];
            Node* currentRoom;
            Node* nodeArray[12];
            struct isPath;
                vector<Node*> nodeVector;

};

#endif

Maze.cpp

#include <iostream>
#include <string>

#include "Maze.h"

using namespace std;

Node* Node1;

void Maze::createMaze(char *inFile){
    int count = 0;

    //Creates Nodes for Maze
    for(int ii = 0; ii <= 12; ii++){
        Node1 = new Node(inFile[count]);
        nodeVector.push_back(Node1);
        count = count + 5;

        //If there is not another node break out of the for loop.
        if(inFile[count] == '\0'){
            break;
        }
    }

}

void Maze::availablePaths(){

}

void Maze::displayPath(){

}

void Maze::moveNorth(){

}

void Maze::moveSouth(){

}

void Maze::moveEast(){

}

void Maze::moveWest(){

}

int Maze::getroomCount(){

}

char Maze::getpathHistory(){

}

char Maze::getcurrentRoom(){

}

Node.h

#ifndef NODE_H
#define NODE_H
#include <string>
#include <map>
#include <sstream>
using namespace std;

class Node
{
        public:
                Node(char);
                void setNodeName(char);
                void attachNewNode(Node, int);
                Node *getAttachedNode(int);
        private:
                char name; // Title that is displayed above the menu.
                Node *attachedNodes[4];
};

#endif

Node.cpp

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

#include "Node.h"
using namespace std;

Node::Node(char name) : name(name) {

} 

void Node::setNodeName(char tempName){
    name = tempName;
}

void Node::attachNewNode(Node temp, int direction){
    attachedNodes[direction] = temp;
}

Node Node::getAttachedNode(int direction){
    return attachedNodes[direction];
}

makefile

#!/bin/bash
#file:makefile
CC = g++
CFLAGS = -c -g

simulate: Main.o Maze.o
    $(CC) Main.o Maze.o -o simulate

Main.o: Main.cpp Maze.h
    $(CC) $(CFLAGS) Main.cpp

Maze.o: Maze.cpp Menu.h Node.h
    $(CC) $(CFLAGS) Maze.cpp
Node.o: Node.cpp Node.h
    $(CC) $(CFLAGS) Node.cpp

clean:
    rm -rf *.o simulate

Answer 1

You can simply fix this by:

export CFLAGS='-gdwarf-2 -gstrict-dwarf'

Then, remake your project.

Answer 2

The problem is not in your code, per se.

One problem is that your linking command is failing because you are not linking all your object files. You need to link Main.o, Maze.o and Node.o to create the executable:

g++ Main.o Maze.o Node.o -o simulate

Another problem is that your compiler is newer than your linker. The compiler is generating debugging information using Dwarf version 4, but your linker (/usr/bin/ld) only understands Dwarf version 2.

/usr/bin/ld: Dwarf Error: found dwarf version '4', this reader only handles
version 2 information.

You need to update your linker to a newer version compatible with the compiler you are using.

Or, as janneb suggests in a comment, you can use -gdwarf-2 in both the compilation and link lines. In the makefile:

CFLAGS = -c -gdwarf-2

FILES.cpp = Main.cpp Maze.cpp Node.cpp
FILES.o   = $(FILES.cpp:.cpp=.o}

simulate: $(FILES.o)
    $(CC) $(CFLAGS) $(FILES.o) -o $@

(There should be few parts of command lines in a makefile that are not macro invocations; then you can change everything more easily.)

You will need to remove the Dwarf-4 object files and recompile to avoid the error/warning.