[Bug c/49413] over-optimization that causes valid code to segfault

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49413

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> 2011-06-15 00:34:37 UTC ---
I think this code is undefined as the alignment requirements of double is 8
bytes but the original (t->xyz->va/t->xyz->vb) is packed so it has a alignment
of 4 bytes.