Also, field_is_valid(field) already does isempty(field), so drop that as
well.
$ SYSTEMD_LOG_LEVEL=debug journalctl -o verbose -F foo-bar-baz
...
Assertion 'field_is_valid(field)' failed at src/libsystemd/sd-journal/sd-journal.c:2789, function sd_journal_query_unique(). Ignoring.
Failed to query unique data objects: Invalid argument
assert_return(j, -EINVAL);
assert_return(!journal_origin_changed(j), -ECHILD);
- assert_return(!isempty(field), -EINVAL);
- assert_return(field_is_valid(field), -EINVAL);
+
+ if (!field_is_valid(field))
+ return -EINVAL;
r = free_and_strdup(&j->unique_field, field);
if (r < 0)