Apparently upstream has made a 2.0.6, and it doesn't seem to suffer from the GTK+ build issue as 2.0.5.
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=81a02f5e9c91592effd7f136e660f89c1c716502 commit 81a02f5e9c91592effd7f136e660f89c1c716502 Author: Andreas Sturmlechner <asturm@gentoo.org> AuthorDate: 2018-12-16 23:49:17 +0000 Commit: Andreas Sturmlechner <asturm@gentoo.org> CommitDate: 2018-12-16 23:53:22 +0000 media-video/guvcview: 2.0.6 version bump Bug: https://bugs.gentoo.org/670674 Closes: https://bugs.gentoo.org/671614 Package-Manager: Portage-2.3.52, Repoman-2.3.12 Signed-off-by: Andreas Sturmlechner <asturm@gentoo.org> media-video/guvcview/Manifest | 1 + media-video/guvcview/guvcview-2.0.6.ebuild | 76 ++++++++++++++++++++++++++++++ 2 files changed, 77 insertions(+)