If a static VLC table gets initialized a second time (or concurrently by
two threads) and if said VLC table uses symbols that have the sign bit
of VLC_TYPE (a typedef for int16_t) set, initializing the VLC fails. The
reason is that the type of the symbol in the temporary array is an
uint16_t and so comparing it to the symbol read from the VLC table will
fail, because only the lower 16bits coincide. Said failure triggers an
assert.
Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@gmail.com>
---
Found when playing around a bit with making the ClearVideo VLCs static.
libavcodec/bitstream.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libavcodec/bitstream.c b/libavcodec/bitstream.c
index 39749c6092..a908c10980 100644
--- a/libavcodec/bitstream.c
+++ b/libavcodec/bitstream.c
@@ -129,7 +129,7 @@ static int alloc_table(VLC *vlc, int size, int use_static)
typedef struct VLCcode {
uint8_t bits;
- uint16_t symbol;
+ VLC_TYPE symbol;
/** codeword, with the first bit-to-be-read in the msb
* (even if intended for a little-endian bitstream reader) */
uint32_t code;
--
2.25.1
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