+2011-12-08 Jonathan Wakely <jwakely.gcc@gmail.com>
+
+ * include/bits/atomic_base.h (__calculate_memory_order): Rename to...
+ (__cmpexch_failure_order): This, and rewrite as constexpr function.
+ (compare_exchange_strong, compare_exchange_weak): Use it.
+ * include/std/atomic (compare_exchange_strong, compare_exchange_weak):
+ Likewise.
+