Re: patch: Re: rfc: auto-casted vector types

[Aldy Hernandez <aldyh at redhat dot com>]

> > Now I see.  Yes, I looked at this approach as well, but this one is
> > more error prone.  V2SI_type_node is all over the place.  We'd add a
> > new type, change the builtins accordingly, and then change
> > is_ev64_opaque_type to recognize this new type as well.  What I am
> > trying to avoid with my approach is changing the back end at all,
> > and just change the user header file.  I also don't want to touch
> > too much what ain't broke (in the back end).
>
> However, I'd rather see us take some trouble now than get in trouble
> down the road.  Having the builtins take a notionally wrong type,
> and having explicit casts all over spe.h, feels like it will
> eventually wind up hurting a lot more.

but changing the header file has the added benefit that if we change 
the opaque type in the future, we only have to change one line (the 
typedef) in the header file.

I honestly don't see too many benefits to changing rs6000.c, and it's 
much more error prone.  But I'm willing to do it that way, if I 
absolutely must.

Aldy