print a big warning if we mess up and run out of space ...

Originally committed as revision 5052 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/dv.c

@@ -886,6 +886,8 @@ static inline void dv_encode_video_segment(DVVideoContext *s,
     for (j=0; j<5*6; j++) {
        if (enc_blks[j].partial_bit_count)
            pb=dv_encode_ac(&enc_blks[j], pb, &pbs[6*5]);
+       if (enc_blks[j].partial_bit_count)
+            av_log(NULL, AV_LOG_ERROR, "ac bitstream overflow\n");
     }
 
     for (j=0; j<5*6; j++)