There are 2 ways to upgrading Gentoo’s profile, which is whether by using the program eselect, or by manual linking.
Firstly the portage tree need to be updated to get the latest profile list by running he following command;
$ sudo emerge --sync
The following example is to update using eselect;
$ sudo eselect profile list $ sudo eselect profile set <number>
where number is the number of favored profile from the list.
To manually update the profile, simply delete the softlink and create a new link to the intended profile as the following (be sure not to add / at the end of /etc/make.profile)
$ sudo rm /etc/make.profile $ sudo ln -s /usr/portage/profiles/<profile of choice> /etc/make.profile
Optionally, in the end you might want to upgrade the system using the new profile;
$ sudo emerge --sync $ sudo emerge --update --newuse --deep world