As a maintainer of graphics/mirtk, could you have a look at PR #252648:
In short, TBB version 2021 will soon be available as devel/onetbb but the port you maintain does not build correctly with it, see the following Poudriere run:
and error logs:
-- Looking for TBB [tbb] (optional)... - not found
Could you try to provide a patch (important: *by replying to this PR*) to facilitate the migration to devel/onetbb ?
To help you modifying your port, expected patches to devel/tbb and devel/onetbb are available in PR #252648.
You will also need suitesparse patches from PR #252651 as suitesparse does not build with oneTbb.
Thanks for your contribution,
Optional dependency on TBB is now OFF by default.
A commit references this bug:
Date: Sun Jan 17 17:16:41 UTC 2021
New revision: 561837
graphics/mirtk: Change the default of the TBB option to OFF until the upstream makes iy oneTBB-compatible.
Reported by: martymac