C++运行示例程序 遇到undefined reference

Question

https://github.com/craigsapp/midifile

此项目下载下来后按照提示在include文件夹里运行了示例程序

#include "MidiFile.h"
#include "Options.h"
#include <iostream>
#include <iomanip>

using namespace std;
using namespace smf;

int main(int argc, char** argv) {
   Options options;
   options.process(argc, argv);
   MidiFile midifile;
   if (options.getArgCount() == 0) midifile.read(cin);
   else midifile.read(options.getArg(1));
   midifile.doTimeAnalysis();
   midifile.linkNotePairs();

   int tracks = midifile.getTrackCount();
   cout << "TPQ: " << midifile.getTicksPerQuarterNote() << endl;
   if (tracks > 1) cout << "TRACKS: " << tracks << endl;
   for (int track=0; track<tracks; track++) {
      if (tracks > 1) cout << "\nTrack " << track << endl;
      cout << "Tick\tSeconds\tDur\tMessage" << endl;
      for (int event=0; event<midifile[track].size(); event++) {
         cout << dec << midifile[track][event].tick;
         cout << '\t' << dec << midifile[track][event].seconds;
         cout << '\t';
         if (midifile[track][event].isNoteOn())
            cout << midifile[track][event].getDurationInSeconds();
         cout << '\t' << hex;
         for (int i=0; i<midifile[track][event].size(); i++)
            cout << (int)midifile[track][event][i] << ' ';
         cout << endl;
      }
   }

   return 0;
}

，但遇到以下错误

C:\Users\JOHN_S~1\AppData\Local\Temp\cchAXKEB.o:example.cpp:(.text+0x3ae): undefined reference to `smf::MidiEventList::operator[](int)'

错误都是这一类型，请问这种错误能从哪儿得到解决，麻烦大神提示一下

Answer 1

这种一般是链接的时候出错 缺少库 可能你没编译库

这项目下边也有步骤 怎么make