c++ 单例模式--构造函数传递参数

c++ 单例模式–构造函数传递参数

// singleton.h

class Singleton: 
{ 
public: 
    static Singleton * GetInstance(MineStrut* pMineStruct) 
    { 
        if (m_pInstance == NULL) {
        m_pInstance = new Singleton(pMineStruct); 
    }
        return m_pInstance; 
    } 

private: 
    Singleton(MineStrut* pMineStruct)
    : m_pMineStruct(m_pMineStruct)
    {
    }

private:    
    MineStrut* m_pMineStruct;
    static Singleton * m_pInstance; 
};

//singleton.cc
Singleton *Singleton::m_pInstance = nullptr;
void Singleton::function() {}
....

class中static Singleton *m_pInstance为申明，需要在singleton.cc中定义它，不然会出现以下错误。
test.cpp:(.text._ZN3Log11getInstanceEmj[_ZN3Log11getInstanceEmj]+0x45): undefined reference to `Singleton::m_pInstance’