[PATCH] Fix PRs 52080, 52097 and 48124, rewrite bitfield expansion, enable the C++ memory model wrt bitfields everywhere

[Eric Botcazou]

> Btw, now checking with gdb, DECL_OFFSET_ALIGN is always 128 for
> all of the fields - that looks bogus.  DECL_ALIGN is 1, but that
> doesn't mean DECL_OFFSET_ALIGN should not be 1 as well, no?

DECL_OFFSET_ALIGN is set to BIGGEST_ALIGNMENT for the first field, see 
start_record_layout.  If DECL_FIELD_OFFSET doesn't change for the next fields, 
DECL_OFFSET_ALIGN will very likely not either.

-- 
Eric Botcazou