what's the trick to get hardlink to use sha256 in docker?

[Curtis Doty]

$ docker run --rm --interactive --tty fedora:39 hardlink -nv /dev/null
cannot initialize sha256 method, use 'memcmp' fallback
Mode:                     dry-run
Method:                   memcmp
Files:                    0
Linked:                   0 files
Compared:                 0 xattrs
Compared:                 0 files
Saved:                    0 B
Duration:                 0.001141 seconds