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[Sylvain Pion <>]

Panagiotis Foteinos a écrit :
> Taking the low level details out, the following code is compiled
> successfully, but throws a segmentation fault (see the dashed arrow below):
>
> *********************************************************************************************************************************************************************
> typedef CGAL::Triangulation_hierarchy_3<Dt>  Dh;
> typedef Dh::Finite_cells_iterator Finite_cells_iterator;
> std::list<Cell_handle*> red_elements;
>
> main()
> {
>     Dh T;
>     //Insert some vertices into T.
>
>     for(Finite_cells_iterator c = T.finite_cells_begin(); i !=
> T.finite_cells_end(); i++)
>        if(c->info().color == red)
>        {
>           Cell_handle* cell_handle_pointer = new Cell_handle();
>           *cell_handle_pointer = c;
>           red_elements.push_back(cell_handle_pointer);
>        }
>
>     //Do stuff with T by removing, inserting, changing the color of some
> elements...
>     //red_elements list is not touched, however.
>
>     for(std::list<Cell_handle*>::iterator i = red_elements.begin(); i !=
> red_elements.end(); i++)
>     {
>        Cell_handle c = **i;
>        if(T.is_cell(c) == false || c->info().color != red)
>          
> red_elements.erase(i);                                                
> ---------------------------------> segmentation fault the first time
> this line is executed.
>     }
>    
> }

Did you try the debug mode of your STL (e.g. -D_GLIBCXX_DEBUG for GCC) ?

You are erasing a list element, and then doing ++ on the iterator
formerly pointing to it => Boom.  A classical problem, not CGAL related.

--
Sylvain Pion
INRIA Sophia-Antipolis
Geometrica Project-Team
CGAL, http://cgal.org/