架构x86_64的未定义符号:编译问题

Question

所以我想开始一项任务,我的教授给我们一个Main.cpp,Main.h,Scanner.cpp,Scanner.h和其他一些实用工具.

我的工作是创建一个Similarity类来使用余弦和Jaccard系数比较文档.但是,我似乎无法正确链接项目,因此我无法启动实际代码.

经过几个小时的努力,看看我做错了什么,我需要新鲜的眼睛看看我做错了什么,我怀疑这是显而易见的.

这是Main.cpp

#include "Main.h"

using namespace std;

static const string TAG = "Main: ";

int main(int argc, char *argv[])
{
  string inStreamName;
  string logStreamName;
  string outStreamName;

  ofstream outStream;
  string timeCallOutput;
  Scanner inStream;

  Similarity similarity;

  ///////////////////////////////////////////////////////////////
  // Boilerplate for naming files and opening files
  Utils::CheckArgs(3, argc, argv, "infilename outfilename logfilename");
  outStreamName = static_cast<string>(argv[2]);
  logStreamName = static_cast<string>(argv[3]);

  Utils::FileOpen(outStream, outStreamName);
  Utils::LogFileOpen(logStreamName);

  timeCallOutput = Utils::timecall("beginning");
  Utils::logStream << timeCallOutput << endl;
  Utils::logStream << TAG << "Beginning execution" << endl;

  Utils::logStream << TAG << "outfile '" << outStreamName << "'" << endl;
  Utils::logStream << TAG << "logfile '" << logStreamName << "'" << endl;
  Utils::logStream.flush();

  ///////////////////////////////////////////////////////////////
  // What follows here is the real work of this code.
  //   read the entire input file and echo it back
  //   compute the two similarity coefficients

  inStreamName = static_cast<string>(argv[1]);
  inStream.openFile(inStreamName);
  Utils::logStream << TAG << "infile '" << inStreamName << "'" << endl;
  Utils::logStream.flush();

  similarity.readData(inStream);

  outStream << TAG << "Data Begin\n" << similarity.toString() << endl;
  outStream << TAG << "Data End\n" << endl;
  outStream.flush();
  inStream.close();

  outStream << TAG << "Begin similarity computation" << endl;
  outStream << TAG << "Maximum Jaccard similarity:\n" <<
                       similarity.maxJaccard() << endl;
  outStream << TAG << "Maximum cosine similarity:\n" <<
                       similarity.maxCosine() << endl;
  outStream << TAG << "End similarity computation" << endl;
  outStream.flush();

  ///////////////////////////////////////////////////////////////
  // Boilerplate for terminating gracefully
  Utils::logStream << TAG << "Ending execution" << endl;
  timeCallOutput = Utils::timecall("ending");
  Utils::logStream << timeCallOutput << endl;
  Utils::logStream.flush();

  outStream.flush();
  Utils::FileClose(outStream);

  Utils::FileClose(Utils::logStream);

  return 0;
}

和Main.h

#ifndef MAIN_H
#define MAIN_H

#include "../../Utilities/Utils.h"
#include "../../Utilities/Scanner.h"

#include "Similarity.h"

class Main
{
public:
  int main();
  virtual ~Main();

private:

};

#endif // MAIN_H

我的相似性.pp

#include "Similarity.h"

using namespace std;

void readData(Scanner& inStream){
}

string maxCosine(){
    return "cosine";
}

string maxJaccard(){
    return "jaccard";
}

string toString(){
    return "toString";
}

最后我的Similarity.h:

#ifndef SIMILARITY_H
#define SIMILARITY_H

#include "../../Utilities/Scanner.h"

class Similarity
{
public:
    Similarity();
    virtual ~Similarity();

    void readData(Scanner& inStream);
    string maxCosine();
    string maxJaccard();
    string toString();
private:

};

#endif

当我使用他提供的makefile,以及我必须使用的makefile以便他的脚本工作来评分它时,我得到这个错误:

g++ -O3 -Wall -o Similarity.o -c Similarity.cpp
g++ -O3 -Wall -o Aprog Main.o Similarity.o Scanner.o ScanLine.o Utils.o 
Undefined symbols for architecture x86_64:
  "Similarity::maxJaccard()", referenced from:
      _main in Main.o
  "Similarity::readData(Scanner&)", referenced from:
      _main in Main.o
  "Similarity::toString()", referenced from:
      _main in Main.o
  "Similarity::maxCosine()", referenced from:
      _main in Main.o
  "Similarity::Similarity()", referenced from:
      _main in Main.o
  "Similarity::~Similarity()", referenced from:
      _main in Main.o
ld: symbol(s) not found for architecture x86_64
collect2: ld returned 1 exit status
make: *** [Aprog] Error 1

感谢您阅读所有内容,我们将非常感谢任何建议或解决方案.

Answer 1

这里没有什么神秘感,链接器告诉你你没有定义丢失的符号,你没有.

Similarity::Similarity()或者Similarity::~Similarity()只是遗失了,你已经错误地定义了其他人,

void Similarity::readData(Scanner& inStream){
}

不

void readData(Scanner& inStream){
}

等等

第二个是名为readData的函数,只有第一个是Similarity类的readData方法.

要清楚这一点,请在Similarity.h中

void readData(Scanner& inStream);

但在Similarity.cpp

void Similarity::readData(Scanner& inStream){
}