QT 程序异常终止

[weixin_38087646]

画图class Plot:public QwtPlot{    Q_OBJECTpublic:    Plot(QWidget *parent = NULL);    virtual ~Plot();    //virtual void replot();    //double draw_square(int x);public Q_SLOTS:    //void setIntervalLength(double);private:    //void initGradient();private:    //QwtInterval d_interval;    //QwtPlotMarker *d_origin;    //QwtPlotCurve *d_curve;};类 Plot继承与QwtPlot，在主程序里什么也没做，运行程序的时候出现“程序异常终止”，具体的编译信息：d:/qt/qtcreator-2.4.1/mingw/bin/../lib/gcc/mingw32/4.4.0/../../../../mingw32/bin/ld.exe: warning: auto-importing has been activated without --enable-auto-import specified on the command line.This should work unless it involves constant data structures referencing symbols from auto-imported DLLs.如果这里的Plot我改为继承与QWidget就不会出现上面的错误，请高手帮忙解答下，都弄了一个晚上了，实在找不到解决方法！