The current version net-libs/nodejs-16.10.0 fails to compile with Clang-13.0.0 and -stdlib=libc++ This issue is reportedly fixed with version 16.11.0 Thanks
ping
16.13.0 was released as LTS for 16.x. https://github.com/nodejs/node/blob/master/doc/changelogs/CHANGELOG_V16.md#16.13.0
https://github.com/gentoo/gentoo/commit/0827d9a8ed0d817b3a83c2563280249a4de89aaf