Crashes in lilv_plugin_get_uis

[jcelerier]

I'm seeing crashes with some plug-ins:

LilvUIs*
lilv_plugin_get_uis(const LilvPlugin* plugin)
{
  lilv_plugin_load_if_necessary(plugin);

  LilvUIs* result = lilv_uis_new();

  SordIter* uis = sord_search(plugin->world->model,
                              plugin->plugin_uri->node,
                              plugin->world->uris.ui_ui,
                              NULL,
                              NULL);

  FOREACH_MATCH (uis) {
    const SordNode* ui = sord_iter_get_node(uis, SORD_OBJECT);

    const SordNode* const type =
      lilv_world_get_unique(plugin->world, ui, plugin->world->uris.rdf_type);
    const SordNode* binary =
      lilv_world_get_unique(plugin->world, ui, plugin->world->uris.lv2_binary);
    if (!binary) {
      binary =
        lilv_world_get_unique(plugin->world, ui, plugin->world->uris.ui_binary);
    }

   // Here binary is still null <-----------------------------------------------------------

    if (sord_node_get_type(ui) != SORD_URI ||
        sord_node_get_type(type) != SORD_URI ||
        sord_node_get_type(binary) != SORD_URI) {  <----------- sord_node_get_type does not seem to null-check
      LILV_ERRORF("Corrupt UI <%s>\n", sord_node_get_string(ui));
      continue;
    }

    LilvUI* const lilv_ui = lilv_ui_new(plugin->world, ui, type, binary);
    zix_tree_insert((ZixTree*)result, lilv_ui, NULL);
  }
  sord_iter_free(uis);

  if (lilv_uis_size(result) > 0) {
    return result;
  }

  lilv_uis_free(result);
  return NULL;
}

In the log I'm seeing:

lilv_world_get_unique(): warning: Subject <http://gareus.org/oss/lv2/fil4#ui_gl> has multiple <http://lv2plug.in/ns/extensions/ui#binary> properties

[jcelerier]

This seems to be caused by having duplicate paths in LV2_PATH: would there be a way to handle "duplicate" plug-ins in a way that isn't going to lead to crashes? For instance sometimes I'll be building a plug-in in my ~ in debug mode.