Initilize a filter

[Bellicano Pascal <pascal_bellicano yahoo fr>]

Here is my code :

       GtkTreeModel *filter_model;
       filter_model=gtk_tree_model_filter_new     
(GTK_TREE_MODEL(store_ori),
                                            NULL);
      
       GtkTreeModelFilter *filter;
       gtk_tree_model_filter_clear_cache(filter);
      
        gtk_tree_view_set_model (GTK_TREE_VIEW(tree_view),    
GTK_TREE_MODEL (filter_model));

         ...........

        gtk_tree_model_filter_set_visible_column 
(GTK_TREE_MODEL_FILTER(filter),7);

         ..........

(store_ori is a liststore)

gcc complains about filter not initialised.. ok but how to initialize it ?