libavformat/mpc8.c:242: error: Uninitialized Value
  The value read from size was never initialized.

libavformat/mpc8.c:242:5: 
240.     avpriv_set_pts_info(st, 32, 1152  << (st->codec->extradata[1]&3)*2, st->codec->sample_rate);
241.     st->duration = c->samples / (1152 << (st->codec->extradata[1]&3)*2);
242.     size -= avio_tell(pb) - pos;
         ^
243. 
244.     if (pb->seekable) {

static int mpc8_read_header(AVFormatContext *s)
{
    MPCContext *c = s->priv_data;
    AVIOContext *pb = s->pb;
    AVStream *st;
    int tag = 0;
    int64_t size, pos;
    c->header_pos = avio_tell(pb);
    if(avio_rl32(pb) != TAG_MPCK){
        av_log(s, AV_LOG_ERROR, "Not a Musepack8 file\n");
        return -1;
    }
    while(!pb->eof_reached){
        pos = avio_tell(pb);
        mpc8_get_chunk_header(pb, &tag, &size);
        if(tag == TAG_STREAMHDR)
            break;
        mpc8_handle_chunk(s, tag, pos, size);
    }
    if(tag != TAG_STREAMHDR){
        av_log(s, AV_LOG_ERROR, "Stream header not found\n");
        return -1;
    }
    pos = avio_tell(pb);
    avio_skip(pb, 4);
    c->ver = avio_r8(pb);
    if(c->ver != 8){
        av_log(s, AV_LOG_ERROR, "Unknown stream version %d\n", c->ver);
        return -1;
    }
    c->samples = ffio_read_varlen(pb);
    ffio_read_varlen(pb);
    st = avformat_new_stream(s, NULL);
    if (!st)
        return AVERROR(ENOMEM);
    st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
    st->codec->codec_id = CODEC_ID_MUSEPACK8;
    st->codec->bits_per_coded_sample = 16;
    st->codec->extradata_size = 2;
    st->codec->extradata = av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
    avio_read(pb, st->codec->extradata, st->codec->extradata_size);
    st->codec->channels = (st->codec->extradata[1] >> 4) + 1;
    st->codec->sample_rate = mpc8_rate[st->codec->extradata[0] >> 5];
    avpriv_set_pts_info(st, 32, 1152  << (st->codec->extradata[1]&3)*2, st->codec->sample_rate);
    st->duration = c->samples / (1152 << (st->codec->extradata[1]&3)*2);
    size -= avio_tell(pb) - pos;
    if (pb->seekable) {
        int64_t pos = avio_tell(s->pb);
        ff_ape_parse_tag(s);
        avio_seek(s->pb, pos, SEEK_SET);
    }
    return 0;
}
['static int mpc8_read_header(AVFormatContext *s)\n{\n    MPCContext *c = s->priv_data;\n    AVIOContext *pb = s->pb;\n    AVStream *st;\n    int tag = 0;\n    int64_t size, pos;\n    c->header_pos = avio_tell(pb);\n    if(avio_rl32(pb) != TAG_MPCK){\n        av_log(s, AV_LOG_ERROR, "Not a Musepack8 file\\n");\n        return -1;\n    }\n    while(!pb->eof_reached){\n        pos = avio_tell(pb);\n        mpc8_get_chunk_header(pb, &tag, &size);\n        if(tag == TAG_STREAMHDR)\n            break;\n        mpc8_handle_chunk(s, tag, pos, size);\n    }\n    if(tag != TAG_STREAMHDR){\n        av_log(s, AV_LOG_ERROR, "Stream header not found\\n");\n        return -1;\n    }\n    pos = avio_tell(pb);\n    avio_skip(pb, 4);\n    c->ver = avio_r8(pb);\n    if(c->ver != 8){\n        av_log(s, AV_LOG_ERROR, "Unknown stream version %d\\n", c->ver);\n        return -1;\n    }\n    c->samples = ffio_read_varlen(pb);\n    ffio_read_varlen(pb);\n    st = avformat_new_stream(s, NULL);\n    if (!st)\n        return AVERROR(ENOMEM);\n    st->codec->codec_type = AVMEDIA_TYPE_AUDIO;\n    st->codec->codec_id = CODEC_ID_MUSEPACK8;\n    st->codec->bits_per_coded_sample = 16;\n    st->codec->extradata_size = 2;\n    st->codec->extradata = av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);\n    avio_read(pb, st->codec->extradata, st->codec->extradata_size);\n    st->codec->channels = (st->codec->extradata[1] >> 4) + 1;\n    st->codec->sample_rate = mpc8_rate[st->codec->extradata[0] >> 5];\n    avpriv_set_pts_info(st, 32, 1152  << (st->codec->extradata[1]&3)*2, st->codec->sample_rate);\n    st->duration = c->samples / (1152 << (st->codec->extradata[1]&3)*2);\n    size -= avio_tell(pb) - pos;\n    if (pb->seekable) {\n        int64_t pos = avio_tell(s->pb);\n        ff_ape_parse_tag(s);\n        avio_seek(s->pb, pos, SEEK_SET);\n    }\n    return 0;\n}']