http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53037
--- Comment #10 from H.J. Lu <hjl.tools at gmail dot com> 2012-04-19 17:20:42 UTC --- Isn't checking alignment of x in: typedef unsigned long long __u64 __attribute__((aligned(4),warn_if_not_aligned(8))); struct foo { int i1; int i2; int i3; __u64 x; }; sufficient for kernel interface purpose? Is there another case we need to check?