libavcodec/dirac.c:159: error: Integer Overflow L2
  ([0, +oo] - 1):unsigned32 by call to `bitstream_read_bit`.

libavcodec/dirac.c:142:1: Parameter `bc->bits_left`
140. /* [DIRAC_STD] 10.3 Parse Source Parameters.
141.  * source_parameters(base_video_format) */
142. static int parse_source_parameters(AVDiracSeqHeader *dsh, BitstreamContext *bc,
     ^
143.                                    void *log_ctx)
144. {

libavcodec/dirac.c:151:9: Call
149.     /* [DIRAC_STD] 10.3.2 Frame size. frame_size(video_params) */
150.     /* [DIRAC_STD] custom_dimensions_flag */
151.     if (bitstream_read_bit(bc)) {
             ^
152.         dsh->width  = get_interleaved_ue_golomb(bc); /* [DIRAC_STD] FRAME_WIDTH  */
153.         dsh->height = get_interleaved_ue_golomb(bc); /* [DIRAC_STD] FRAME_HEIGHT */

libavcodec/bitstream.h:145:1: Parameter `bc->bits_left`
  143. 
  144. /* Return one bit from the buffer. */
  145. static inline unsigned bitstream_read_bit(BitstreamContext *bc)
       ^
  146. {
  147.     if (!bc->bits_left)

libavcodec/bitstream.h:150:12: Call
  148.         refill_64(bc);
  149. 
  150.     return get_val(bc, 1);
                  ^
  151. }
  152. 

libavcodec/bitstream.h:130:1: Parameter `n`
    128. }
    129. 
    130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
         ^
    131. {
    132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:139:5: Assignment
    137.     bc->bits <<= n;
    138. #endif
    139.     bc->bits_left -= n;
             ^
    140. 
    141.     return ret;

libavcodec/dirac.c:159:9: Call
157.      *  chroma_sampling_format(video_params) */
158.     /* [DIRAC_STD] custom_chroma_format_flag */
159.     if (bitstream_read_bit(bc))
             ^
160.         /* [DIRAC_STD] CHROMA_FORMAT_INDEX */
161.         dsh->chroma_format = get_interleaved_ue_golomb(bc);

libavcodec/bitstream.h:145:1: Parameter `bc->bits_left`
  143. 
  144. /* Return one bit from the buffer. */
  145. static inline unsigned bitstream_read_bit(BitstreamContext *bc)
       ^
  146. {
  147.     if (!bc->bits_left)

libavcodec/bitstream.h:150:12: Call
  148.         refill_64(bc);
  149. 
  150.     return get_val(bc, 1);
                  ^
  151. }
  152. 

libavcodec/bitstream.h:130:1: <LHS trace>
128. }
129. 
130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
     ^
131. {
132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:130:1: Parameter `bc->bits_left`
    128. }
    129. 
    130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
         ^
    131. {
    132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:130:1: <RHS trace>
128. }
129. 
130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
     ^
131. {
132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:130:1: Parameter `n`
    128. }
    129. 
    130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
         ^
    131. {
    132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:139:5: Binary operation: ([0, +oo] - 1):unsigned32 by call to `bitstream_read_bit` 
    137.     bc->bits <<= n;
    138. #endif
    139.     bc->bits_left -= n;
             ^
    140. 
    141.     return ret;
