[gentoo-user] Installing asdf & uiop without urged to install sbcl / update package.provided for each version

Hi,

I am installing sbcl directly from the authors source,
because I want the then created pdf docs (emerge
only installs html docs).

I emerge sbcl, asfd, uiop with emerge, bootstrapped/installed
sbcl manually to /usr/local, emerge -C sbcl, depcleaned asdf
uiop (and other stuff) and emerged asdf, uiop again, which
put an entry of them into world and depclean will no long
offer them for removing.

But asdf, uiop alone make no sense in the eyes of emerge
and it pulls sbcl again -- which is reasonable for one
not looking additionally at /usr/local :)

There is package.provided to give emerge the OK, to
not longe speculate about the existence the world and everything
and take 42 things as given.
But as far as I understood the syntax there, one has
to specify any single version of a package and if you miss
one it gets installed.

Masking a needed package (from emerge point of view) isn't
that nice also, since with every sync one will get that
nasty warnings, that a needed package is masked.

Any clean way around this?

Thanks a lot for any help in advance!
Cheers
Meino