James Almer: > On 3/22/2021 3:35 AM, Andreas Rheinhardt wrote: >> 88d80cb97528d52dac3178cf5393d6095eca6200 changed the type of >> PutBitContext.BitBuf to uint64_t; it used to be an uint32_t. >> While said structure is not public, it is nevertheless used by >> certain avpriv functions and therefore crosses library boundaries: >> avpriv_align_put_bits and avpriv_copy_bits were used in other libraries >> in release 4.3 (and at the time of 88d80cb9) and so this commit broke >> ABI. >> >> This commit mitigates the trouble caused by this by using an uint32_t >> again, but only for the 4.4 release branch and not the master branch, >> as doing so for master, would break the ABI of master again, although >> it is very unlikely that anyone would be helped by this (there don't >> seem to be any users that combine libavcodec built from master and >> libavformat from an old release: otherwise we would have received bug >> reports about said ABI break). > > So basically, this would only be a problem if your application loads > lavf <= 4.3 (that was linked to lavc <= 4.3) alongside lavc 4.4 at > runtime, right? >
lavfi also used avpriv_align_put_bits up until 8129c32e488645db325263a6bee01311b83e7ed9, so lavfi <= 4.3 is dangerous, too, if combined with lavc 4.4. >> >> Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@gmail.com> >> --- >> Important: This is only intended for the 4.4 release branch. >> >> libavcodec/put_bits.h | 7 ------- >> 1 file changed, 7 deletions(-) >> >> diff --git a/libavcodec/put_bits.h b/libavcodec/put_bits.h >> index cd66a82a44..f07944a8fb 100644 >> --- a/libavcodec/put_bits.h >> +++ b/libavcodec/put_bits.h >> @@ -35,16 +35,9 @@ >> #include "version.h" >> -#if ARCH_X86_64 >> -// TODO: Benchmark and optionally enable on other 64-bit architectures. >> -typedef uint64_t BitBuf; >> -#define AV_WBBUF AV_WB64 >> -#define AV_WLBUF AV_WL64 >> -#else >> typedef uint32_t BitBuf; >> #define AV_WBBUF AV_WB32 >> #define AV_WLBUF AV_WL32 >> -#endif >> static const int BUF_BITS = 8 * sizeof(BitBuf); > > LGTM _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
