> -----Original Message----- > From: ffmpeg-devel [mailto:ffmpeg-devel-boun...@ffmpeg.org] On Behalf Of > Reimar Döffinger > Sent: Friday, June 07, 2019 11:07 PM > To: FFmpeg development discussions and patches <ffmpeg-devel@ffmpeg.org> > Subject: Re: [FFmpeg-devel] [PATCH v4] vaapi_encode_mjpeg: fix bad component > id bug > > On 07.06.2019, at 23:45, "U. Artie Eoff" <ullysses.a.e...@intel.com> wrote: > > > The compound literals assigned to "components" > > only exist within the scope of the if/else > > block (thanks Mark Thompson for the better > > explanation). > > > > Thus, after this if/else block, "components" > > ends up pointing to an arbitrary/undefined > > array. With some compilers and depending on > > optimization settings, these arbitrary values > > may end up being the same value (i.e. 0 with > > GNU GCC 9.x). Unfortunately, the GNU GCC > > compiler, at least, never prints any warnings > > about this. > > > > This patch fixes this issue by assigning the > > constant arrays to local variables at function > > scope and then pointing "components" to those > > as necessary. > > > > Fixes #7915 > > > > Signed-off-by: U. Artie Eoff <ullysses.a.e...@intel.com> > > --- > > libavcodec/vaapi_encode_mjpeg.c | 6 ++++-- > > 1 file changed, 4 insertions(+), 2 deletions(-) > > > > diff --git a/libavcodec/vaapi_encode_mjpeg.c > > b/libavcodec/vaapi_encode_mjpeg.c > > index 4dcdc3d16bb0..bd029cc90315 100644 > > --- a/libavcodec/vaapi_encode_mjpeg.c > > +++ b/libavcodec/vaapi_encode_mjpeg.c > > @@ -227,6 +227,8 @@ static int > > vaapi_encode_mjpeg_init_picture_params(AVCodecContext *avctx, > > JPEGRawScanHeader *sh = &priv->scan.header; > > VAEncPictureParameterBufferJPEG *vpic = pic->codec_picture_params; > > const AVPixFmtDescriptor *desc; > > + const uint8_t components_rgb[3] = { 'R', 'G', 'B' }; > > + const uint8_t components_yuv[3] = { 1, 2, 3 }; > > Not sure what the necessary scope is for these, but maybe safest to go for > "static const"?
I don't think these need scope beyond this function since the values are just "copied" into the frame header here. So static would just be an [barely detectable] optimization. Unless I am missing something? > _______________________________________________ > 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". _______________________________________________ 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".
