libavcodec/mpegvideo.c:644: error: Uninitialized Value
  The value read from y_size was never initialized.

libavcodec/mpegvideo.c:644:13: 
642.             FF_ALLOCZ_OR_GOTO(s->avctx, s->dc_val_base, yc_size * sizeof(int16_t), fail);
643.             s->dc_val[0] = s->dc_val_base + s->b8_stride + 1;
644.             s->dc_val[1] = s->dc_val_base + y_size + s->mb_stride + 1;
                 ^
645.             s->dc_val[2] = s->dc_val[1] + c_size;
646.             for(i=0;i<yc_size;i++)

int MPV_common_init(MpegEncContext *s)
{
    int y_size, c_size, yc_size, i, mb_array_size, mv_table_size, x, y, threads;
    if(s->codec_id == CODEC_ID_MPEG2VIDEO && !s->progressive_sequence)
        s->mb_height = (s->height + 31) / 32 * 2;
    else if (s->codec_id != CODEC_ID_H264)
        s->mb_height = (s->height + 15) / 16;
    if(s->avctx->pix_fmt == PIX_FMT_NONE){
        av_log(s->avctx, AV_LOG_ERROR, "decoding to PIX_FMT_NONE is not supported.\n");
        return -1;
    }
    if(s->avctx->thread_count > MAX_THREADS || (s->avctx->thread_count > s->mb_height && s->mb_height)){
        av_log(s->avctx, AV_LOG_ERROR, "too many threads\n");
        return -1;
    }
    if((s->width || s->height) && av_image_check_size(s->width, s->height, 0, s->avctx))
        return -1;
    dsputil_init(&s->dsp, s->avctx);
    ff_dct_common_init(s);
    s->flags= s->avctx->flags;
    s->flags2= s->avctx->flags2;
    if (s->width && s->height) {
        s->mb_width  = (s->width  + 15) / 16;
        s->mb_stride = s->mb_width + 1;
        s->b8_stride = s->mb_width*2 + 1;
        s->b4_stride = s->mb_width*4 + 1;
        mb_array_size= s->mb_height * s->mb_stride;
        mv_table_size= (s->mb_height+2) * s->mb_stride + 1;
        avcodec_get_chroma_sub_sample(s->avctx->pix_fmt,&(s->chroma_x_shift),
                                      &(s->chroma_y_shift) );
        s->h_edge_pos= s->mb_width*16;
        s->v_edge_pos= s->mb_height*16;
        s->mb_num = s->mb_width * s->mb_height;
        s->block_wrap[0]=
        s->block_wrap[1]=
        s->block_wrap[2]=
        s->block_wrap[3]= s->b8_stride;
        s->block_wrap[4]=
        s->block_wrap[5]= s->mb_stride;
        y_size = s->b8_stride * (2 * s->mb_height + 1);
        c_size = s->mb_stride * (s->mb_height + 1);
        yc_size = y_size + 2 * c_size;
        s->codec_tag = ff_toupper4(s->avctx->codec_tag);
        s->stream_codec_tag = ff_toupper4(s->avctx->stream_codec_tag);
        s->avctx->coded_frame= (AVFrame*)&s->current_picture;
        FF_ALLOCZ_OR_GOTO(s->avctx, s->mb_index2xy, (s->mb_num+1)*sizeof(int), fail)
        for(y=0; y<s->mb_height; y++){
            for(x=0; x<s->mb_width; x++){
                s->mb_index2xy[ x + y*s->mb_width ] = x + y*s->mb_stride;
            }
        }
        s->mb_index2xy[ s->mb_height*s->mb_width ] = (s->mb_height-1)*s->mb_stride + s->mb_width;
        if (s->encoding) {
            FF_ALLOCZ_OR_GOTO(s->avctx, s->p_mv_table_base            , mv_table_size * 2 * sizeof(int16_t), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->b_forw_mv_table_base       , mv_table_size * 2 * sizeof(int16_t), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->b_back_mv_table_base       , mv_table_size * 2 * sizeof(int16_t), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->b_bidir_forw_mv_table_base , mv_table_size * 2 * sizeof(int16_t), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->b_bidir_back_mv_table_base , mv_table_size * 2 * sizeof(int16_t), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->b_direct_mv_table_base     , mv_table_size * 2 * sizeof(int16_t), fail)
            s->p_mv_table           = s->p_mv_table_base            + s->mb_stride + 1;
            s->b_forw_mv_table      = s->b_forw_mv_table_base       + s->mb_stride + 1;
            s->b_back_mv_table      = s->b_back_mv_table_base       + s->mb_stride + 1;
            s->b_bidir_forw_mv_table= s->b_bidir_forw_mv_table_base + s->mb_stride + 1;
            s->b_bidir_back_mv_table= s->b_bidir_back_mv_table_base + s->mb_stride + 1;
            s->b_direct_mv_table    = s->b_direct_mv_table_base     + s->mb_stride + 1;
            if(s->msmpeg4_version){
                FF_ALLOCZ_OR_GOTO(s->avctx, s->ac_stats, 2*2*(MAX_LEVEL+1)*(MAX_RUN+1)*2*sizeof(int), fail);
            }
            FF_ALLOCZ_OR_GOTO(s->avctx, s->avctx->stats_out, 256, fail);
            FF_ALLOCZ_OR_GOTO(s->avctx, s->mb_type  , mb_array_size * sizeof(uint16_t), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->lambda_table, mb_array_size * sizeof(int), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->q_intra_matrix  , 64*32   * sizeof(int), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->q_inter_matrix  , 64*32   * sizeof(int), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->q_intra_matrix16, 64*32*2 * sizeof(uint16_t), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->q_inter_matrix16, 64*32*2 * sizeof(uint16_t), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->input_picture, MAX_PICTURE_COUNT * sizeof(Picture*), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->reordered_input_picture, MAX_PICTURE_COUNT * sizeof(Picture*), fail)
            if(s->avctx->noise_reduction){
                FF_ALLOCZ_OR_GOTO(s->avctx, s->dct_offset, 2 * 64 * sizeof(uint16_t), fail)
            }
        }
    }
    FF_ALLOCZ_OR_GOTO(s->avctx, s->picture, MAX_PICTURE_COUNT * sizeof(Picture), fail)
    for(i = 0; i < MAX_PICTURE_COUNT; i++) {
        avcodec_get_frame_defaults((AVFrame *)&s->picture[i]);
    }
    if (s->width && s->height) {
        FF_ALLOCZ_OR_GOTO(s->avctx, s->error_status_table, mb_array_size*sizeof(uint8_t), fail)
        if(s->codec_id==CODEC_ID_MPEG4 || (s->flags & CODEC_FLAG_INTERLACED_ME)){
            for(i=0; i<2; i++){
                int j, k;
                for(j=0; j<2; j++){
                    for(k=0; k<2; k++){
                        FF_ALLOCZ_OR_GOTO(s->avctx,    s->b_field_mv_table_base[i][j][k], mv_table_size * 2 * sizeof(int16_t), fail)
                        s->b_field_mv_table[i][j][k] = s->b_field_mv_table_base[i][j][k] + s->mb_stride + 1;
                    }
                    FF_ALLOCZ_OR_GOTO(s->avctx, s->b_field_select_table [i][j], mb_array_size * 2 * sizeof(uint8_t), fail)
                    FF_ALLOCZ_OR_GOTO(s->avctx, s->p_field_mv_table_base[i][j], mv_table_size * 2 * sizeof(int16_t), fail)
                    s->p_field_mv_table[i][j] = s->p_field_mv_table_base[i][j]+ s->mb_stride + 1;
                }
                FF_ALLOCZ_OR_GOTO(s->avctx, s->p_field_select_table[i], mb_array_size * 2 * sizeof(uint8_t), fail)
            }
        }
        if (s->out_format == FMT_H263) {
            FF_ALLOCZ_OR_GOTO(s->avctx, s->coded_block_base, y_size, fail);
            s->coded_block= s->coded_block_base + s->b8_stride + 1;
            FF_ALLOCZ_OR_GOTO(s->avctx, s->cbp_table     , mb_array_size * sizeof(uint8_t), fail)
            FF_ALLOCZ_OR_GOTO(s->avctx, s->pred_dir_table, mb_array_size * sizeof(uint8_t), fail)
        }
        if (s->h263_pred || s->h263_plus || !s->encoding) {
            FF_ALLOCZ_OR_GOTO(s->avctx, s->dc_val_base, yc_size * sizeof(int16_t), fail);
            s->dc_val[0] = s->dc_val_base + s->b8_stride + 1;
            s->dc_val[1] = s->dc_val_base + y_size + s->mb_stride + 1;
            s->dc_val[2] = s->dc_val[1] + c_size;
            for(i=0;i<yc_size;i++)
                s->dc_val_base[i] = 1024;
        }
        FF_ALLOCZ_OR_GOTO(s->avctx, s->mbintra_table, mb_array_size, fail);
        memset(s->mbintra_table, 1, mb_array_size);
        FF_ALLOCZ_OR_GOTO(s->avctx, s->mbskip_table, mb_array_size+2, fail);
        FF_ALLOCZ_OR_GOTO(s->avctx, s->prev_pict_types, PREV_PICT_TYPES_BUFFER_SIZE, fail);
        s->parse_context.state= -1;
        if((s->avctx->debug&(FF_DEBUG_VIS_QP|FF_DEBUG_VIS_MB_TYPE)) || (s->avctx->debug_mv)){
            s->visualization_buffer[0] = av_malloc((s->mb_width*16 + 2*EDGE_WIDTH) * s->mb_height*16 + 2*EDGE_WIDTH);
            s->visualization_buffer[1] = av_malloc((s->mb_width*16 + 2*EDGE_WIDTH) * s->mb_height*16 + 2*EDGE_WIDTH);
            s->visualization_buffer[2] = av_malloc((s->mb_width*16 + 2*EDGE_WIDTH) * s->mb_height*16 + 2*EDGE_WIDTH);
        }
    }
    s->context_initialized = 1;
    if (s->width && s->height) {
        s->thread_context[0]= s;
        threads = s->avctx->thread_count;
        for(i=1; i<threads; i++){
            s->thread_context[i]= av_malloc(sizeof(MpegEncContext));
            memcpy(s->thread_context[i], s, sizeof(MpegEncContext));
        }
        for(i=0; i<threads; i++){
            if(init_duplicate_context(s->thread_context[i], s) < 0)
                goto fail;
            s->thread_context[i]->start_mb_y= (s->mb_height*(i  ) + s->avctx->thread_count/2) / s->avctx->thread_count;
            s->thread_context[i]->end_mb_y  = (s->mb_height*(i+1) + s->avctx->thread_count/2) / s->avctx->thread_count;
        }
    }
    return 0;
 fail:
    MPV_common_end(s);
    return -1;
}
['int MPV_common_init(MpegEncContext *s)\n{\n    int y_size, c_size, yc_size, i, mb_array_size, mv_table_size, x, y, threads;\n    if(s->codec_id == CODEC_ID_MPEG2VIDEO && !s->progressive_sequence)\n        s->mb_height = (s->height + 31) / 32 * 2;\n    else if (s->codec_id != CODEC_ID_H264)\n        s->mb_height = (s->height + 15) / 16;\n    if(s->avctx->pix_fmt == PIX_FMT_NONE){\n        av_log(s->avctx, AV_LOG_ERROR, "decoding to PIX_FMT_NONE is not supported.\\n");\n        return -1;\n    }\n    if(s->avctx->thread_count > MAX_THREADS || (s->avctx->thread_count > s->mb_height && s->mb_height)){\n        av_log(s->avctx, AV_LOG_ERROR, "too many threads\\n");\n        return -1;\n    }\n    if((s->width || s->height) && av_image_check_size(s->width, s->height, 0, s->avctx))\n        return -1;\n    dsputil_init(&s->dsp, s->avctx);\n    ff_dct_common_init(s);\n    s->flags= s->avctx->flags;\n    s->flags2= s->avctx->flags2;\n    if (s->width && s->height) {\n        s->mb_width  = (s->width  + 15) / 16;\n        s->mb_stride = s->mb_width + 1;\n        s->b8_stride = s->mb_width*2 + 1;\n        s->b4_stride = s->mb_width*4 + 1;\n        mb_array_size= s->mb_height * s->mb_stride;\n        mv_table_size= (s->mb_height+2) * s->mb_stride + 1;\n        avcodec_get_chroma_sub_sample(s->avctx->pix_fmt,&(s->chroma_x_shift),\n                                      &(s->chroma_y_shift) );\n        s->h_edge_pos= s->mb_width*16;\n        s->v_edge_pos= s->mb_height*16;\n        s->mb_num = s->mb_width * s->mb_height;\n        s->block_wrap[0]=\n        s->block_wrap[1]=\n        s->block_wrap[2]=\n        s->block_wrap[3]= s->b8_stride;\n        s->block_wrap[4]=\n        s->block_wrap[5]= s->mb_stride;\n        y_size = s->b8_stride * (2 * s->mb_height + 1);\n        c_size = s->mb_stride * (s->mb_height + 1);\n        yc_size = y_size + 2 * c_size;\n        s->codec_tag = ff_toupper4(s->avctx->codec_tag);\n        s->stream_codec_tag = ff_toupper4(s->avctx->stream_codec_tag);\n        s->avctx->coded_frame= (AVFrame*)&s->current_picture;\n        FF_ALLOCZ_OR_GOTO(s->avctx, s->mb_index2xy, (s->mb_num+1)*sizeof(int), fail)\n        for(y=0; y<s->mb_height; y++){\n            for(x=0; x<s->mb_width; x++){\n                s->mb_index2xy[ x + y*s->mb_width ] = x + y*s->mb_stride;\n            }\n        }\n        s->mb_index2xy[ s->mb_height*s->mb_width ] = (s->mb_height-1)*s->mb_stride + s->mb_width;\n        if (s->encoding) {\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->p_mv_table_base            , mv_table_size * 2 * sizeof(int16_t), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->b_forw_mv_table_base       , mv_table_size * 2 * sizeof(int16_t), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->b_back_mv_table_base       , mv_table_size * 2 * sizeof(int16_t), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->b_bidir_forw_mv_table_base , mv_table_size * 2 * sizeof(int16_t), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->b_bidir_back_mv_table_base , mv_table_size * 2 * sizeof(int16_t), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->b_direct_mv_table_base     , mv_table_size * 2 * sizeof(int16_t), fail)\n            s->p_mv_table           = s->p_mv_table_base            + s->mb_stride + 1;\n            s->b_forw_mv_table      = s->b_forw_mv_table_base       + s->mb_stride + 1;\n            s->b_back_mv_table      = s->b_back_mv_table_base       + s->mb_stride + 1;\n            s->b_bidir_forw_mv_table= s->b_bidir_forw_mv_table_base + s->mb_stride + 1;\n            s->b_bidir_back_mv_table= s->b_bidir_back_mv_table_base + s->mb_stride + 1;\n            s->b_direct_mv_table    = s->b_direct_mv_table_base     + s->mb_stride + 1;\n            if(s->msmpeg4_version){\n                FF_ALLOCZ_OR_GOTO(s->avctx, s->ac_stats, 2*2*(MAX_LEVEL+1)*(MAX_RUN+1)*2*sizeof(int), fail);\n            }\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->avctx->stats_out, 256, fail);\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->mb_type  , mb_array_size * sizeof(uint16_t), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->lambda_table, mb_array_size * sizeof(int), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->q_intra_matrix  , 64*32   * sizeof(int), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->q_inter_matrix  , 64*32   * sizeof(int), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->q_intra_matrix16, 64*32*2 * sizeof(uint16_t), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->q_inter_matrix16, 64*32*2 * sizeof(uint16_t), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->input_picture, MAX_PICTURE_COUNT * sizeof(Picture*), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->reordered_input_picture, MAX_PICTURE_COUNT * sizeof(Picture*), fail)\n            if(s->avctx->noise_reduction){\n                FF_ALLOCZ_OR_GOTO(s->avctx, s->dct_offset, 2 * 64 * sizeof(uint16_t), fail)\n            }\n        }\n    }\n    FF_ALLOCZ_OR_GOTO(s->avctx, s->picture, MAX_PICTURE_COUNT * sizeof(Picture), fail)\n    for(i = 0; i < MAX_PICTURE_COUNT; i++) {\n        avcodec_get_frame_defaults((AVFrame *)&s->picture[i]);\n    }\n    if (s->width && s->height) {\n        FF_ALLOCZ_OR_GOTO(s->avctx, s->error_status_table, mb_array_size*sizeof(uint8_t), fail)\n        if(s->codec_id==CODEC_ID_MPEG4 || (s->flags & CODEC_FLAG_INTERLACED_ME)){\n            for(i=0; i<2; i++){\n                int j, k;\n                for(j=0; j<2; j++){\n                    for(k=0; k<2; k++){\n                        FF_ALLOCZ_OR_GOTO(s->avctx,    s->b_field_mv_table_base[i][j][k], mv_table_size * 2 * sizeof(int16_t), fail)\n                        s->b_field_mv_table[i][j][k] = s->b_field_mv_table_base[i][j][k] + s->mb_stride + 1;\n                    }\n                    FF_ALLOCZ_OR_GOTO(s->avctx, s->b_field_select_table [i][j], mb_array_size * 2 * sizeof(uint8_t), fail)\n                    FF_ALLOCZ_OR_GOTO(s->avctx, s->p_field_mv_table_base[i][j], mv_table_size * 2 * sizeof(int16_t), fail)\n                    s->p_field_mv_table[i][j] = s->p_field_mv_table_base[i][j]+ s->mb_stride + 1;\n                }\n                FF_ALLOCZ_OR_GOTO(s->avctx, s->p_field_select_table[i], mb_array_size * 2 * sizeof(uint8_t), fail)\n            }\n        }\n        if (s->out_format == FMT_H263) {\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->coded_block_base, y_size, fail);\n            s->coded_block= s->coded_block_base + s->b8_stride + 1;\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->cbp_table     , mb_array_size * sizeof(uint8_t), fail)\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->pred_dir_table, mb_array_size * sizeof(uint8_t), fail)\n        }\n        if (s->h263_pred || s->h263_plus || !s->encoding) {\n            FF_ALLOCZ_OR_GOTO(s->avctx, s->dc_val_base, yc_size * sizeof(int16_t), fail);\n            s->dc_val[0] = s->dc_val_base + s->b8_stride + 1;\n            s->dc_val[1] = s->dc_val_base + y_size + s->mb_stride + 1;\n            s->dc_val[2] = s->dc_val[1] + c_size;\n            for(i=0;i<yc_size;i++)\n                s->dc_val_base[i] = 1024;\n        }\n        FF_ALLOCZ_OR_GOTO(s->avctx, s->mbintra_table, mb_array_size, fail);\n        memset(s->mbintra_table, 1, mb_array_size);\n        FF_ALLOCZ_OR_GOTO(s->avctx, s->mbskip_table, mb_array_size+2, fail);\n        FF_ALLOCZ_OR_GOTO(s->avctx, s->prev_pict_types, PREV_PICT_TYPES_BUFFER_SIZE, fail);\n        s->parse_context.state= -1;\n        if((s->avctx->debug&(FF_DEBUG_VIS_QP|FF_DEBUG_VIS_MB_TYPE)) || (s->avctx->debug_mv)){\n            s->visualization_buffer[0] = av_malloc((s->mb_width*16 + 2*EDGE_WIDTH) * s->mb_height*16 + 2*EDGE_WIDTH);\n            s->visualization_buffer[1] = av_malloc((s->mb_width*16 + 2*EDGE_WIDTH) * s->mb_height*16 + 2*EDGE_WIDTH);\n            s->visualization_buffer[2] = av_malloc((s->mb_width*16 + 2*EDGE_WIDTH) * s->mb_height*16 + 2*EDGE_WIDTH);\n        }\n    }\n    s->context_initialized = 1;\n    if (s->width && s->height) {\n        s->thread_context[0]= s;\n        threads = s->avctx->thread_count;\n        for(i=1; i<threads; i++){\n            s->thread_context[i]= av_malloc(sizeof(MpegEncContext));\n            memcpy(s->thread_context[i], s, sizeof(MpegEncContext));\n        }\n        for(i=0; i<threads; i++){\n            if(init_duplicate_context(s->thread_context[i], s) < 0)\n                goto fail;\n            s->thread_context[i]->start_mb_y= (s->mb_height*(i  ) + s->avctx->thread_count/2) / s->avctx->thread_count;\n            s->thread_context[i]->end_mb_y  = (s->mb_height*(i+1) + s->avctx->thread_count/2) / s->avctx->thread_count;\n        }\n    }\n    return 0;\n fail:\n    MPV_common_end(s);\n    return -1;\n}']