OX5F703EBF指令引用的“0XCDCDCDD1”内存不能为READ

在头文件中定义：
CDengluDlg(CWnd* pParent = NULL);   // standard constructor
CDengluDlg(CMySet* pSet,CWnd* pParent = NULL);   // standard constructor
CMySet* m_pSet1;在实现文件中：
CDengluDlg::CDengluDlg(CWnd* pParent  /*=NULL*/)
: CDialog(CDengluDlg::IDD, pParent)
{
//{{AFX_DATA_INIT(CDengluDlg)
m_cheliangchandi = _T("");
m_cheliangleibie = _T("");
m_cheliangleixing = _T("");
m_cheshenyanse = _T("");
m_jianceleibie = _T("");
m_ranyouleibie = _T("");
m_shiyongzhuangkuang = _T("");
m_chepaihaoma = _T("");
m_chezhudanwei = _T("");
m_dipanhaoma = _T("");
m_edinggonglv = _T("");
m_fadongjihao = _T("");
m_jianceyuanhao = _T("");
m_jiancezhanming = _T("");
m_lianxifangshi = _T("");
m_lichengdushu = _T("");
m_zhengchezhongliang = _T("");
//}}AFX_DATA_INIT
}CDengluDlg::CDengluDlg(CMySet* pSet,CWnd* pParent  /*=NULL*/)
: CDialog(CDengluDlg::IDD, pParent)
{
//{{AFX_DATA_INIT(CDengluDlg)
m_cheliangchandi = _T("");
m_cheliangleibie = _T("");
m_cheliangleixing = _T("");
m_cheshenyanse = _T("");
m_jianceleibie = _T("");
m_ranyouleibie = _T("");
m_shiyongzhuangkuang = _T("");
m_chepaihaoma = _T("");
m_chezhudanwei = _T("");
m_dipanhaoma = _T("");
m_edinggonglv = _T("");
m_fadongjihao = _T("");
m_jianceyuanhao = _T("");
m_jiancezhanming = _T("");
m_lianxifangshi = _T("");
m_lichengdushu = _T("");
m_zhengchezhongliang = _T("");
//}}AFX_DATA_INIT
m_pSet1=pSet;
}而后调用m_pSet1时报错，说OX5F703EBF指令引用的“0XCDCDCDD1”内存不能为READ，
是不是内存没用分配对？请问如何解决？