#include <stdlib.h>
#include <string>
#include <iostream>
#include <QDebug>
using namespace std;

class Teacher
{
public:
  Teacher(string name = "ti", int _age = 100);
  Teacher(const Teacher &tea);

  const double m_dPi;

};

Teacher::Teacher(string name, int _age)
  :m_dPi(8)
{

   cout << "teacher init is run !\n" << endl;
}

Teacher::Teacher(const Teacher &tea)
{
    cout <<"Teacher::Teacher(const Teacher &tea)"<<endl;
}

int main()
{
   Teacher t;
   Teacher t1 = t;

}

 我发现 把 const double m_dPi;改成 double m_dPi;就可以了，

但是不知道为什么？