uutils ln -f unlinks an existing destination before attempting a hard link, so a missing source deletes the destination even though link creation fails.
GNU ln attempts linking first and only removes and retries when replacement is actually possible.

Reproduction Steps

touch /tmp/ln_dst && ln -f /tmp/nonexistent_source /tmp/ln_dst
# Expected (GNU): reports missing source, prints exit=1, and still lists /tmp/ln_dst
# Actual (uutils): reports hard-link creation failure, prints exit=1, and /tmp/ln_dst is missing

Impact

ln -f can silently destroy existing files when the source path is wrong or disappears, breaking GNU compatibility and causing data loss in scripts that rely on force-replace semantics.