Infer bitfied order from architecture instead of checking it at configure time.

Author: insertinterestingnamehere

config/qthread_check_bitfield_order.m4

@@ -614,7 +614,6 @@ esac
 AS_IF([test "x$enable_hardware_atomics" != xno],
       [QTHREAD_CHECK_ATOMICS($sizeof_aligned_t)])
 QTHREAD_VAMACROS
-QTHREAD_CHECK_BITFIELDS
 
 QTHREAD_MALLOC_ATTRIBUTE
 QTHREAD_UNUSED_ATTRIBUTE

configure.ac

@@ -29,11 +29,15 @@
 /* Allow functions to be inlined */
 #undef QINLINE
 
-/* Define if bitfields are in forward order */
-#undef BITFIELD_ORDER_FORWARD
-
-/* Define if bitfields are in reverse order */
-#undef BITFIELD_ORDER_REVERSE
+#ifndef __powerpc
+#define BITFIELD_ORDER_REVERSE
+#else
+// ARM processors can technically change modes between
+// big-endian and little-endian which also reverses the
+// bitfield order. The overwhelming majority of the time
+// they're run in little-endian mode though.
+#define BITFIELD_ORDER_FORWARD
+#endif
 
 /* The size of `void*', as computed by sizeof. */
 #undef SIZEOF_VOIDP