Drupal 8.0.0 beta 12. More info: https://www.drupal.org/node/2514176

core/lib/Drupal/Component/Uuid/Com.php

@@ -0,0 +1,23 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Component\Uuid\Com.
+ */
+
+namespace Drupal\Component\Uuid;
+
+/**
+ * UUID implementation using the Windows internal GUID extension.
+ *
+ * @see http://php.net/com_create_guid
+ */
+class Com implements UuidInterface {
+  /**
+   * {@inheritdoc}
+   */
+  public function generate() {
+    // Remove {} wrapper and make lower case to keep result consistent.
+    return strtolower(trim(com_create_guid(), '{}'));
+  }
+}