tree.h (DECL_OFFSET_ALIGN): Make the off_align field of the tree structure an exponent rather than an...

* tree.h (DECL_OFFSET_ALIGN): Make the off_align field of
the tree structure an exponent rather than an explicit alignment
so it doesn't overflow.
(SET_DECL_OFFSET_ALIGN): New macro.
* stor-layout.c (place_union_field): Use SET_DECL_OFFSET_ALIGN
rather than DECL_OFFSET_ALIGN.
(place_field): Likewise.
* expmed.c (store_bit_field): Abort on align==0 to avoid
antisocial machine behaviour.

From-SVN: r35659