[FFmpeg-devel] [PATCH v2] lavc/qsv: suppress code scan complain

[Li, Zhong]

> From: ffmpeg-devel [mailto:ffmpeg-devel-bounces at ffmpeg.org] On Behalf
> Of Carl Eugen Hoyos
> Sent: Thursday, May 24, 2018 5:33 PM
> To: FFmpeg development discussions and patches
> <ffmpeg-devel at ffmpeg.org>
> Subject: Re: [FFmpeg-devel] [PATCH v2] lavc/qsv: suppress code scan
> complain
> 
> 2018-05-24 10:35 GMT+02:00, Li, Zhong <zhong.li at intel.com>:
> >> From: ffmpeg-devel [mailto:ffmpeg-devel-bounces at ffmpeg.org] On
> Behalf
> >> Of Carl Eugen Hoyos
> >> Sent: Wednesday, May 23, 2018 8:32 PM
> >> To: FFmpeg development discussions and patches
> >> <ffmpeg-devel at ffmpeg.org>
> >> Subject: Re: [FFmpeg-devel] [PATCH v2] lavc/qsv: suppress code scan
> >> complain
> >>
> >> 2018-05-23 12:46 GMT+02:00, Zhong Li <zhong.li at intel.com>:
> >> > Suppress the complain "variables 'type' is used but maybe
> >> > uninitialized".
> >> > ---
> >> >  libavcodec/qsv.c | 5 ++++-
> >> >  1 file changed, 4 insertions(+), 1 deletion(-)
> >> >
> >> > diff --git a/libavcodec/qsv.c b/libavcodec/qsv.c index
> >> > 45e1c25..3ff4f2c 100644
> >> > --- a/libavcodec/qsv.c
> >> > +++ b/libavcodec/qsv.c
> >> > @@ -31,6 +31,7 @@
> >> >  #include "libavutil/hwcontext.h"
> >> >  #include "libavutil/hwcontext_qsv.h"
> >> >  #include "libavutil/imgutils.h"
> >> > +#include "libavutil/avassert.h"
> >> >
> >> >  #include "avcodec.h"
> >> >  #include "qsv_internal.h"
> >> > @@ -197,7 +198,7 @@ int ff_qsv_find_surface_idx(QSVFramesContext
> >> *ctx,
> >> > QSVFrame *frame)
> >> >
> >> >  enum AVPictureType ff_qsv_map_pictype(int mfx_pic_type)  {
> >> > -    enum AVPictureType type;
> >> > +    enum AVPictureType type = AV_PICTURE_TYPE_NONE;
> >> >      switch (mfx_pic_type & 0x7) {
> >> >      case MFX_FRAMETYPE_I:
> >> >          if (mfx_pic_type & MFX_FRAMETYPE_S) @@ -214,6 +215,8
> >> @@ enum
> >> > AVPictureType ff_qsv_map_pictype(int mfx_pic_type)
> >> >          else
> >> >              type = AV_PICTURE_TYPE_P;
> >> >          break;
> >> > +    default:
> >> > +        av_assert0(0);
> >>
> >> I didn't test but I would have expected that exactly one of these
> >> changes is sufficient to silence the warning, no?
> >
> > Thanks for review. It is not a compile warning and just found by
> > Coverity Scan, I've double-confirmed this patch is useful to suppress
> > the code scan complain.
> 
> Of course, I understand.
> 
> My question was if one of the two changes (ie either the variable
> initialization or the assert) isn't enough to suppress the code scan complain.

I've confirmed that, running scan again. The complain is disappeared now.

> 
> Carl Eugen