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

[Carl Eugen Hoyos]

2018-05-24 11:39 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: 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.

Then why did you push both changes instead of only one of them?

Carl Eugen