[middle-end] PR c/29092, vector types not compatible when they should be

[Andrew Pinski]

> 
> 
> Hi Paolo,
> 
> On Wed, 27 Sep 2006, Paolo Bonzini wrote:
> http://gcc.gnu.org/ml/gcc-patches/2006-09/msg01215.html
> > 2006-09-25  Paolo Bonzini  <bonzini@gnu.org>
> >
> >	PR c/29092
> >	* tree.c (make_vector_type): Memoize types.
> >	(used_vector_types): New.
> 
> Hmm.  I'm not really happy with the way that you're using the front-end
> specific types_compatible_p langhook to decide whether to create a new
> VECTOR_TYPE node or not.  The middle-end, and particulary new type
> construction in tree.c has/needs a stricter type system...

Shouldn't this be more like what we do for arrays?  Note I have not
looked into how we deal with arrays but I know that we can do
make_array_type and have it return the same array type twice.

-- Pinski