test_util_fgets_eagain fails on FreeBSD 0.2.9

It looks like on FreeBSD, this test is failing because fgets is returning NULL upon EAGAIN: https://jenkins.torproject.org/view/Failed+Unstable/job/tor-ci-freebsd-amd64-0.2.9/33/consoleFull

09:31:49 util/fgets_eagain: 
09:31:49   FAIL ../tor/src/test/test_util.c:3963: assert(retptr OP_EQ buf): 0x0 vs 0x7fffffffe404

That test block is:

  /* Send in a partial line */
  retlen = write(test_pipe[1], "A", 1);
  tt_int_op(retlen, OP_EQ, 1);
  retptr = fgets(buf, sizeof(buf), test_stream);
  tt_int_op(errno, OP_EQ, EAGAIN);
  tt_ptr_op(retptr, OP_EQ, buf);
  tt_str_op(buf, OP_EQ, "A");
  errno = 0;

This test appears absent on 0.3.3 now. I'm not sure what this failure means here. Is FreeBSD just different, or is this an actual issue?