[Bug tree-optimization/53970] -ftree-vectorization does not handle well unaligned data

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53970

--- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-07-16 14:53:21 UTC ---
The only hint we have on the a->l[i] expression that it involves a packed
aggregate is DECL_ALIGN of the 'l' FIELD_DECL and TYPE_ALIGN of mystruct
itself.  Nowhere we have a TYPE/DECL_PACKED flag set.  That is because how
pragma pack works - it simply adjusts the global maximum_field_alignment
of stor-layout.c.

That means that expr.c:contains_packed_reference does not work.