[FFmpeg-trac] #9458(avcodec:reopened): ffmpeg's outputs differ a lot when compiled with gcc and clang

[FFmpeg]

#9458: ffmpeg's outputs differ a lot when compiled with gcc and clang
------------------------------------+------------------------------------
             Reporter:  Shaohua Li  |                    Owner:  (none)
                 Type:  defect      |                   Status:  reopened
             Priority:  normal      |                Component:  avcodec
              Version:  git-master  |               Resolution:
             Keywords:  race        |               Blocked By:
             Blocking:              |  Reproduced by developer:  0
Analyzed by developer:  0           |
------------------------------------+------------------------------------
Changes (by mkver):

 * keywords:   => race
 * resolution:  invalid =>
 * status:  closed => reopened
 * component:  undetermined => avcodec

Comment:

 It's a race in the MPEG-4 encoder (and as such unreproducible with one
 encoder thread). Reads in ff_mpeg4_pred_dc() are not synced with writes in
 ff_mpeg4_pred_dc() as well as ff_clean_intra_table_entries(). The same
 races happen in the vsynth*-mpeg4-thread-tests (with x from 1..3, _lena).
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/9458#comment:7>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker