Question on accessing and using binfos

[<Primrose dot Mbanefo at Infineon dot com>]

Hello,

I'm wondering if I can get information from here on how to use the binfo
macros.

These two macros, BINFO_BASE_BINFO and BINFO_BASE_ITERATE, are mentioned
on the onlinedocs webpage but I can't find any header file describing
them which means the compilation always fails.
Are they still current? Or should I use something else instead? (I have
gcc 3.4.1)

How should these macros be used? If class A is mother class to B with
the assosciated trees being Atree and Btree repectively, does
TYPE_BINFO(Btree) give Atree?
Or should BINFO_BASE_BINFO(TYPE_BINFO(Btree)) give Atree?
And what does BINFO_TYPE actually do? (sorry but I don't really
understand the instructions on the webpage...)

I would also like information on accessing trees from their types.
A library acting as backend to GCC gives me access to a class C's tree,
let's say Ctree.
I would like to know if C is derived from D. normally I should do,
same_type-p(Ctree, Dtree) {I guess...}
but I don't have or don't know how to get the Dtree. I just know that
the name of the class is D.
Is there a macro for retrieving the tree representing a class from its
name or any known way of doing such a thing?

Thanks for any answers.

Primrose