This is specified in the package's setup.py: https://github.com/gitpython-developers/gitdb/blob/master/setup.py#L23 Any package that needs to use gitdb will fail since 4.0.0 was added to the tree. Solution for now is to mask >=dev-python/smmap-4.0.0.
Can you try stripping the dep to see if it’s genuinely needed?
I do question whether it's really needed as well, this <4 was set about a year ago and "seem" like a just-in-case safety.
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=7d8979be42cabdcacc64663d28be3108c3cd89a2 commit 7d8979be42cabdcacc64663d28be3108c3cd89a2 Author: Michał Górny <mgorny@gentoo.org> AuthorDate: 2021-01-31 08:57:59 +0000 Commit: Michał Górny <mgorny@gentoo.org> CommitDate: 2021-01-31 08:57:59 +0000 dev-python/gitdb: Remove smmap upper bound Closes: https://bugs.gentoo.org/767970 Signed-off-by: Michał Górny <mgorny@gentoo.org> dev-python/gitdb/{gitdb-4.0.5.ebuild => gitdb-4.0.5-r1.ebuild} | 7 +++++++ 1 file changed, 7 insertions(+)