+At the moment, bup will ignore Linux attributes (cf. chattr(1) and
+lsattr(1)) on some systems (any big-endian systems where sizeof(long)
+< sizeof(int)). This is because the Linux kernel and FUSE currently
+disagree over the type of the attr system call arguments, and so on
+big-endian systems there's no way to get the results without the risk
+of stack corruption (http://lwn.net/Articles/575846/). In these
+situations, bup will print a warning the first time Linux attrs are
+relevant during any index/save/restore operation.
+