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

[Richard Guenther]

On Mon, 26 Mar 2012, Eric Botcazou wrote:

> > The patch looks reasonable - can we compute this backward from the
> > result of the outer get_inner_reference call and the outermost
> > field-decl though?  Or make get_inner_reference compute that while
> > analyzing the full reference and return a flag?  OTOH it shouldn't
> > be too expensive.
> 
> There are a lot of calls to get_inner_reference throughout the compiler though.
> And it is cheap if you compare it with the 4.7 code, which essentially does the 
> same processing for _every_ field in the record (and even if the record object 
> isn't a handled_component_p).

Yes, indeed.  One of the main motivation was to get rid of that quadratic
complexity ...

Richard.