+ * C implementation of the lock-free skiplist data-structure created by Maurice Herlihy,
+ * Yossi Lev, and Nir Shavit. See "The Art of Multiprocessor Programming"
+ * http://www.amazon.com/Art-Multiprocessor-Programming-Maurice-Herlihy/dp/0123705916/
+ *
+ * See also Kir Fraser's dissertation "Practical Lock Freedom"
+ * www.cl.cam.ac.uk/techreports/UCAM-CL-TR-579.pdf
+ *
+ * This code depends on certain stores and loads being ordered. Be careful on non-x86 platforms
+ * with weaker memory-models. This code probably won't work without adding some memory barriers.