获取Dwarf错误版本'4‘

Question

我的学校项目出了点问题。我认为这可能是我使用指针的错误，但我不确定为什么我会得到这个错误。这段代码是不完整的，但我一直在尝试测试它。你知道为什么我会收到这个错误吗?它意味着什么？谢谢!

来自Cygwin终端的错误

-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

问题本身并不在你的代码中。

一个问题是，您的链接命令失败，因为您没有链接所有的目标文件。您需要链接Main.o、Maze.o和Node.o来创建可执行文件：

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

另一个问题是你的编译器比链接器新。编译器正在使用Dwarf版本4生成调试信息，但您的链接器(/usr/bin/ld)只能理解Dwarf版本2。

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

您需要将链接器更新为与您正在使用的编译器兼容的更新版本。

或者，正如janneb在comment中建议的那样，您可以在编译和链接行中使用-gdwarf-2。在makefile中

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 $@

( makefile中应该只有很少一部分命令行不是宏调用；这样您就可以更容易地更改所有内容。)

您将需要删除Dwarf-4目标文件并重新编译，以避免出现错误/警告。

Answer 2

您可以通过以下方式简单地解决此问题：

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

然后，重写你的项目。