I've tested it for a while now, since https://bugs.gentoo.org/711782 works great for me on a rpi4 arm64
*** Bug 722148 has been marked as a duplicate of this bug. ***
Unable to check for sanity: > no match for package: =sci-mathematics/genius-1.0.15
Sanity check failed: > sci-mathematics/genius-1.0.25 > depend ~arm64 stable profile default/linux/arm64/17.0 (9 total) > gui-libs/amtk:5 > rdepend ~arm64 stable profile default/linux/arm64/17.0 (9 total) > gui-libs/amtk:5
~arm64 added, closing