Anton Khirnov:
> Quoting Andreas Rheinhardt (2020-10-27 11:30:32)
>> Andreas Rheinhardt:
>>> 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;
>>>
>> LGTM'ed by Lynne via email and pushed.
>
> This is the second time I see this, why does that not go through the ML?
>
I don't know. Seems like Lynne has some trouble with her MUA.
- Andreas
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