emerge --sync
>>> Syncing repository 'gentoo' into '/var/db/repos/gentoo'...
 * Using keys from /usr/share/openpgp-keys/gentoo-release.asc
 * Refreshing keys via WKD ...                                                                                                                                            [ !! ]
 * Refreshing keys from keyserver hkps://keys.gentoo.org ...OpenPGP keyring refresh failed:
gpg: refreshing 4 keys from hkps://keys.gentoo.org
gpg: keyserver refresh failed: General error

OpenPGP keyring refresh failed:
gpg: refreshing 4 keys from hkps://keys.gentoo.org
gpg: keyserver refresh failed: General error

OpenPGP keyring refresh failed:
gpg: refreshing 4 keys from hkps://keys.gentoo.org
gpg: keyserver refresh failed: General error

OpenPGP keyring refresh failed:
gpg: refreshing 4 keys from hkps://keys.gentoo.org
gpg: keyserver refresh failed: General error

OpenPGP keyring refresh failed:
gpg: refreshing 4 keys from hkps://keys.gentoo.org
gpg: keyserver refresh failed: General error

OpenPGP keyring refresh failed:
gpg: refreshing 4 keys from hkps://keys.gentoo.org
gpg: keyserver refresh failed: General error 

Die Neukompilierung von gnutls brachte eine Lösung