Merge commit 'dad12ce4'

* commit 'dad12ce4':
  movenc: Print a warning for an unhandled case of nonzero start dts with empty_moov

Conflicts:
	libavformat/movenc.c
Merged-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/movenc.c

@@ -3849,8 +3849,14 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
     if (!trk->entry && trk->start_dts == AV_NOPTS_VALUE && !supports_edts(mov)) {
         trk->cluster[trk->entry].dts = trk->start_dts = 0;
     }
-    if (trk->start_dts == AV_NOPTS_VALUE)
+    if (trk->start_dts == AV_NOPTS_VALUE) {
         trk->start_dts = pkt->dts;
+        if (pkt->dts && mov->flags & FF_MOV_FLAG_EMPTY_MOOV)
+            av_log(s, AV_LOG_WARNING,
+                   "Track %d starts with a nonzero dts %"PRId64". This "
+                   "currently isn't handled correctly in combination with "
+                   "empty_moov.\n", pkt->stream_index, pkt->dts);
+    }
     trk->track_duration = pkt->dts - trk->start_dts + pkt->duration;
     trk->last_sample_is_subtitle_end = 0;