While does it segfaults

[Fabio Rotondo <mlists rotondo it>]

Hi list,

 could anyone please tell me why this piece of code segfaults?

Do the following:

1 - Run the app
2 - Move the vscrollbar (in the middle)
3 - Press the button
4 - Try to move the vscrollbar again -> segfault

Thanks,

 Fabio


/*
 * DO NOT EDIT THIS FILE - it is generated by Glade.
 */

#include <string.h>
#include <gtk/gtk.h>


  GtkWidget *clist1;
  GtkWidget *scrolledwindow1;

void show ( GtkWidget * w )
{
        GtkAdjustment * adj;
        GtkAdjustment a;

        adj = gtk_scrolled_window_get_vadjustment ( GTK_SCROLLED_WINDOW ( scrolledwindow1 ) );
        
        memcpy ( &a, adj, sizeof ( GtkAdjustment ) );

        printf ( "Value: %f\n", a.value );

        a.value = 39.0;

  gtk_scrolled_window_set_vadjustment ( GTK_SCROLLED_WINDOW ( scrolledwindow1 ), &a );
        
}

int main ( int argc, char * argv[] )
{
  GtkWidget *window1;
  GtkWidget *vbox1;
  GtkWidget *label3;
  GtkWidget *label4;
  GtkWidget *label5;
  GtkWidget *button1;
        int t;
        char * a[4];

        gtk_init ( &argc, &argv );

  window1 = gtk_window_new (GTK_WINDOW_TOPLEVEL);
  gtk_object_set_data (GTK_OBJECT (window1), "window1", window1);

  vbox1 = gtk_vbox_new (FALSE, 0);
  gtk_container_add (GTK_CONTAINER (window1), vbox1);

  scrolledwindow1 = gtk_scrolled_window_new (NULL, NULL);
  gtk_widget_show (scrolledwindow1);
  gtk_box_pack_start (GTK_BOX (vbox1), scrolledwindow1, TRUE, TRUE, 0);

  clist1 = gtk_clist_new (3);
  gtk_container_add (GTK_CONTAINER (scrolledwindow1), clist1);
  gtk_clist_set_column_width (GTK_CLIST (clist1), 0, 80);
  gtk_clist_set_column_width (GTK_CLIST (clist1), 1, 80);
  gtk_clist_set_column_width (GTK_CLIST (clist1), 2, 80);
  gtk_clist_column_titles_show (GTK_CLIST (clist1));

  label3 = gtk_label_new ("label3");
  gtk_clist_set_column_widget (GTK_CLIST (clist1), 0, label3);

  label4 = gtk_label_new ("label4");
  gtk_clist_set_column_widget (GTK_CLIST (clist1), 1, label4);

  label5 = gtk_label_new ("label5");
  gtk_clist_set_column_widget (GTK_CLIST (clist1), 2, label5);

  button1 = gtk_button_new_with_label ("button1");
  gtk_box_pack_start (GTK_BOX (vbox1), button1, FALSE, FALSE, 0);

        gtk_signal_connect ( GTK_OBJECT ( button1 ), "clicked", show, NULL );

        a[0] = "one";
        a[1] = "two";
        a[2] = "three";

        for ( t = 0; t < 40; t++)
                gtk_clist_append ( GTK_CLIST ( clist1 ), a );

        gtk_widget_show_all ( window1 );

        gtk_main ();

}