pango_layout_get_line_count () segfault

[emj10 vt edu]

Hey all,

I am attempting to display text with modified letter spacing using an attribute
list and a font description.  However, I'm not sure if I'm using the
pango_attr_letter_spacing_new (), pango_layout_set_attributes (), or
pango_layout_set_font_description () calls correctly as I am receiving a
segmentation fault when I attempt to call pango_layout_get_line_count ().

Am I using these functions incorrectly? Also, would a simple workaround to avoid
using an attribute list be adding markup to the text when calling
pango_layout_set_text ()?

The backtrace shows the actual segmentation fault coming from
pango_attribute_copy (), which was called by pango_attr_list_copy (), which was
called from pango_layout_get_line_count ().

Thanks in advance,
Eric


static gboolean
draw(GtkWidget *widget,
     GdkEventConfigure *event,
     gpointer data)
{
  cairo_surface_t *surface;
  cairo_t         *cr;

  surface = cairo_image_surface_create(CAIRO_FORMAT_ARGB32,128,64);
  cr = cairo_create(surface);

  switch(cairo_status(cr))
  {
    case CAIRO_STATUS_SUCCESS:
    {
      PangoLayout          *layout;
      PangoFontDescription *desc;
      PangoAttrList        *attr_list;
      PangoAttribute       *spacing;
      unsigned char        *data;

      layout = pango_cairo_create_layout(cr);
      if (!layout)
      {
          fprintf(stderr,"draw(): ");
          fprintf(stderr,"Could not create pango-layout!\n");
          break;
      }

      desc = pango_font_description_new();
      if (!desc)
      {
          fprintf(stderr,"draw(): ");
          fprintf(stderr,"Could not create pango-font-description!\n");
          break;
      }

      spacing = pango_attr_letter_spacing_new(5);
      pango_attr_list_change(attr_list, spacing);
      pango_font_description_set_absolute_size(desc, 16 * PANGO_SCALE);
      pango_font_description_set_family(desc, "Arial");
      pango_font_description_set_weight(desc, PANGO_WEIGHT_ULTRALIGHT);
      pango_font_description_set_style(desc, PANGO_STYLE_NORMAL);
      pango_layout_set_attributes(layout, attr_list);
      pango_layout_set_font_description (layout, desc);
      pango_layout_set_text (layout, "Display some text", -1);

      cairo_set_source_rgb(cr, 0.5, 0.0, 0.5);
      cairo_move_to(cr, 10, 25);

      fprintf(stderr, "layout line count:%d\n",
pango_layout_get_line_count(layout));
      pango_cairo_show_layout_line(cr, pango_layout_get_line(layout,0));

      pango_attribute_destroy(spacing);
      pango_attr_list_unref(attr_list);
      pango_font_description_free (desc);
      g_object_unref (layout);
    }
  }
  cairo_destroy(cr);
  cairo_surface_destroy(surface);
  return FALSE;
}