[Bug c/51628] __attribute__((packed)) is unsafe in some cases

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51628

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> 2011-12-19 
23:27:24 UTC ---
I think this is just undefined at runtime which means we can only warn about
it.  Which we do with -Walign