Hello, when I make, the output does not show exactly where is the problem:working:. here is the output of "make": /usr/lib/qt-3.3/bin/moc -o VVc_demo.moc VVc_demo.cpp g++ -I../../include -I../../../Arrangement_2/include -ggdb -Wall '-I/home/naderan/CGAL-3.2/include/CGAL/config/i686_Linux-2.6_g++-3.3.3' '-I/home/naderan/CGAL-3.2/include' -I/usr/X11R6/include -I/usr/lib/qt-3.3/include -DCGAL_USE_CGAL_CORE -c VVc_demo.cpp VVc_demo.cpp: In member function `virtual void VVc_window::mousePressEvent(QMouseEvent*)': VVc_demo.cpp:254: warning: unused variable `int numberOfPoints' VVc_demo.cpp:234: warning: unused variable `double len2' VVc_demo.cpp:234: warning: unused variable `double len3' VVc_demo.cpp: In member function `void VVc_window::redraw_win()': VVc_demo.cpp:410: error: request for member `drawLine' in ` this->VVc_window::widget', which is of non-aggregate type `CGAL::Qt_widget*' ../../include/CGAL/VVc_diagram_2.h: In member function `void CGAL::VVc_diagram_2<Traits_, AppKernel_>::queryMahmood(typename CGAL::Polygon_clearance_offsetting_2<Traits_>::Alg_point_2&, typename CGAL::Polygon_clearance_offsetting_2<Traits_>::Alg_point_2&, double&, std::vector<typename CGAL::Polygon_clearance_offsetting_2<Traits_>::Alg_point_2, std::allocator<typename CGAL::Polygon_clearance_offsetting_2<Traits_>::Alg_point_2> >) const [with Traits_ = Traits_2, AppKernel_ = App_kernel]': VVc_demo.cpp:289: instantiated from here ../../include/CGAL/VVc_diagram_2.h:956: warning: unused variable `bool flag' make: *** [VVc_demo.o] Error 1%-| So where is the error???:confused: the warning should not produce ant error. Regards, mahmood -- View this message in context: http://www.nabble.com/where-is-the-error---tp14546579p14546579.html Sent from the gcc - Help mailing list archive at Nabble.com.