Strict warning: Only variables should be passed by reference in asset_type_form() (line 65 of /asset/includes/asset.admin.inc).

I open this issue to report a little bug, really easy to solve
It's a common problem see this blog post for more information (in french)

Problem/Motivation

When I add a new asset type I have this Warning:

Strict warning: Only variables should be passed by reference in asset_type_form() (line 65 of /asset/includes/asset.admin.inc).

Proposed resolution

Line 57 asset.admin.inc we have this code :

  $icons_options = array('none' => t('No icon'));
  $module_icons = _assets_get_icons();
  if (!empty($module_icons)) {
    $icons_options = $icons_options + $module_icons;
  }

  $form['icons']['icon'] = array(
    '#type' => 'radios',
    '#default_value' => $asset_type->icon ? $asset_type->icon : reset(array_keys($icons_options)),
    '#options' => $icons_options,
    '#title' => t('Button icon'),
  );

Just change to this :

  $icons_options = array('none' => t('No icon'));
  $module_icons = _assets_get_icons();
  if (!empty($module_icons)) {
    $icons_options = $icons_options + $module_icons;
  }

  $icons_options = array_keys($icons_options);

  $form['icons']['icon'] = array(
    '#type' => 'radios',
    '#default_value' => $asset_type->icon ? $asset_type->icon : reset($icons_options),
    '#options' => $icons_options,
    '#title' => t('Button icon'),
  );

and hop the warning disappear :)