[gentoo-user] emerge problem - removing old libraries?

[Helmut Jarausch]

Hi,

even the most recent portage  2.2.0_alpha90 has difficulties handling  
@preserved-rebuild especially after many binary emerge operations.
It tries to re-emerge the same packages again and again.
As a last resort I have to remove  
/var/lib/portage/preserved_libs_registry.
But after that the old libraries are still hanging around and  
revdep-rebuild won't since there aren't any broken libs or binaries  
just some which are linked against old versions.
Is there an elegant way to find these old libraries? (Removing them  
would alert revdep-rebuild afterwards).

Thanks for a hint,
Helmut.