Gtk-CRITICAL - getting meaningful information

[Mick <bareman tpg com au>]

I've been using gtk for a while and frequently get messages like this:
(nuchimp2:2621): Gtk-CRITICAL **: gtk_text_view_get_buffer: assertion
`GTK_IS_TEXT_VIEW (text_view)' failed
some times I can stumble over the cause and solution but the rest of
the time I'm left to blindly grope around in the dark.

Is there any way to get something meaningful that will point to a real
world location. I assume the :2621 points to a location in the code but
two successive compilations with the source unchanged (eg: make clean;
make; make install; run; make clean; make; make install; run) results
in a different number.

I used glade to define the interface:
...
  <object class="GtkWindow" id="chimp_window">
    <property name="title" translatable="yes">Chimp for
chatmunkees</property> <property name="default_width">640</property>
    <property name="default_height">400</property>
    <property name="icon">pixmaps/chimp2.xpm</property>
    <signal name="destroy" handler="gtk_main_quit"/>
    <child>
      <object class="GtkVBox" id="vbox1">
        <property name="visible">True</property>
        <property name="orientation">vertical</property>
...
        <child>
          <object class="GtkNotebook" id="notebook1">
            <property name="visible">True</property>
            <property name="can_focus">True</property>
            <child>
              <object class="GtkVBox" id="vbox2">
                <property name="visible">True</property>
                <property name="orientation">vertical</property>
                <child>
                  <object class="GtkHPaned" id="hpaned1">
                    <property name="visible">True</property>
                    <property name="can_focus">True</property>
                    <child>
                      <object class="GtkTextView" id="chat_view">
                        <property name="visible">True</property>
                        <property name="can_focus">True</property>
                        <property name="buffer">chat_buffer</property>
                      </object>
                      <packing>
                        <property name="resize">True</property>
                        <property name="shrink">False</property>
                      </packing>
                    </child>
...
                  </object>
                  <packing>
                    <property name="position">0</property>
                  </packing>
                </child>
...
  <object class="GtkTextTagTable" id="chattexttagtable"/>
...
  <object class="GtkTextBuffer" id="chat_buffer">
    <property name="tag_table">chattexttagtable</property>
  </object>
</interface>
the code snippet this particular instance comes from is:

GtkTextView *chat_view;
GtkTextBuffer *chat_buffer;
GtkTextIter start, end;
GtkTextIter iter;

main()
{
...
chimp_window = GTK_WIDGET(gtk_builder_get_object(builder,
"chimp_window")); gtk_builder_connect_signals(builder, NULL);          
gtk_widget_show(chimp_window);

chat_buffer = gtk_text_view_get_buffer(GTK_TEXT_VIEW(chat_view));
gtk_text_buffer_create_tag(chat_buffer, "blue_fg", "foreground",
"blue", NULL); gtk_text_buffer_insert_with_tags_by_name(chat_buffer,
&iter, "Colored Text\n", -1, "blue_fg", "lmarg",  NULL); ...
}

which gives these:
(nuchimp2:2621): Gtk-CRITICAL **: gtk_text_view_get_buffer: assertion
`GTK_IS_TEXT_VIEW (text_view)' failed

(nuchimp2:2621): Gtk-CRITICAL **: gtk_text_buffer_create_tag: assertion
`GTK_IS_TEXT_BUFFER (buffer)' failed

(nuchimp2:2621): Gtk-CRITICAL **:
gtk_text_buffer_insert_with_tags_by_name: assertion `GTK_IS_TEXT_BUFFER
(buffer)' failed

the tarball of the package (the small part I've done so far) can be d/l
from http:/www.junkyardalchemy.org/nuchimp2-0.1.tar.gz in case I've
snipped something critical.