https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=311516b5b875c60eda5579eae21a3b9adc5bbcff added wget-1.16.3-r2.ebuild with REQUIRED_USE="?? ( gnutls libressl )", which is overriden by later assignment of this variable (inherited from older ebuilds). $ grep REQUIRED_USE= wget-1.16.3-r2.ebuild REQUIRED_USE="?? ( gnutls libressl )" REQUIRED_USE="ntlm? ( !gnutls ssl ) gnutls? ( ssl )"
it's also invalid as ?? is new to EAPI=5. i rewrote it like so: http://gitweb.gentoo.org/repo/gentoo.git/commit/?id=c7c7949830cc0bd1022e4f1dc8efe374ada818e7