When doing segment seeking in a FLAC file (the segment stop point is set exactly to the duration of the file), flacdec does not send SEGMENT_DONE message when reaching the stop point, but sends EOS message instead.

While it may seem right to send EOS, because there's EOS after the last nanosecond, the more right behaviour, I think, would be to send SEGMENT_DONE message. Besides, some plugins react exactly that way, i. e. oggdemux:

gst-plugins-base/ext/ogg/gstoggdemux.c (2681):

eos:
  {
    ret = GST_FLOW_OK;
    /* segment playback just posts a segment end message instead of
     * pushing out EOS. */
    ogg->segment_running = FALSE;
    if (ogg->segment.flags & GST_SEEK_FLAG_SEGMENT) {
      gint64 stop;

      if ((stop = ogg->segment.stop) == -1)
        stop = ogg->segment.duration;

      GST_LOG_OBJECT (ogg, "Sending segment done, at end of segment");
      gst_element_post_message (GST_ELEMENT (ogg),
          gst_message_new_segment_done (GST_OBJECT (ogg), GST_FORMAT_TIME,
              stop));
    } else {
      GST_LOG_OBJECT (ogg, "Sending EOS, at end of stream");
      gst_ogg_demux_send_event (ogg, gst_event_new_eos ());
    }
    goto pause;
  }

Unfortunately, I do not fully understand flacdec source to write a patch myself, but I hope this information may be useful to the developers.