Why Linux executable googleearth can't find proper libstdc++.so.6 ?

[Yuri]

b. f. wrote:
>
> That entry also says that Fedora 8 can be used,  which was the latest
> Linux base port at the time the entry was made, and the skype port
> Makefile says Fedora Core 6 __or later__ can be used.  So presumably
> later Linux base ports will also work: try the most recent Linux base
> emulation port that is available for your platform.
>   

With those lines in /etc/make.conf:
OVERRIDE_LINUX_BASE_PORT=f10
OVERRIDE_LINUX_NONBASE_PORTS=f10
everything works. But with f8 there were still problems.

How would people know that they should set f10?

Ideally this should be done my portupgrade.
Or, at the very least, there should be a corresponding record in 
/usr/pots/UPGRADING.
Record 20090831 mentions f10 in connection with some other port, but not 
as a general recommendation.

Yuri