libcxxrt is no longer maintained upstream. It used to be needed to maintain ABI in Gentoo/FreeBSD but that is no longer supported. Plus, FreeBSD maintains their own fork anyway.
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=e13c6bd7773345f10df84984e3361f922ac04178 commit e13c6bd7773345f10df84984e3361f922ac04178 Author: Michał Górny <mgorny@gentoo.org> AuthorDate: 2020-01-12 11:45:11 +0000 Commit: Michał Górny <mgorny@gentoo.org> CommitDate: 2020-01-12 11:48:12 +0000 package.mask: Last rite sys-libs/libcxxrt Bug: https://bugs.gentoo.org/705268 Signed-off-by: Michał Górny <mgorny@gentoo.org> profiles/package.mask | 9 +++++++++ 1 file changed, 9 insertions(+)
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=48ccdc1f2319ff1303cd1dc0c9cf8258d3a028f0 commit 48ccdc1f2319ff1303cd1dc0c9cf8258d3a028f0 Author: Michał Górny <mgorny@gentoo.org> AuthorDate: 2020-02-13 17:43:09 +0000 Commit: Michał Górny <mgorny@gentoo.org> CommitDate: 2020-02-13 17:43:09 +0000 sys-libs/libcxxrt: Remove last-rited pkg Closes: https://bugs.gentoo.org/705268 Signed-off-by: Michał Górny <mgorny@gentoo.org> profiles/package.mask | 9 --- sys-libs/libcxxrt/Manifest | 1 - sys-libs/libcxxrt/files/Makefile | 23 ------- sys-libs/libcxxrt/files/Makefile.test | 7 -- sys-libs/libcxxrt/files/prepare_snapshot.sh | 16 ----- sys-libs/libcxxrt/libcxxrt-0.0_p20180311.ebuild | 88 ------------------------- sys-libs/libcxxrt/libcxxrt-9999.ebuild | 88 ------------------------- sys-libs/libcxxrt/metadata.xml | 18 ----- 8 files changed, 250 deletions(-)