[FFmpeg-devel] [PATCH 01/12] Make av_d2q() manage the case where d is infinite.

[Stefano Sabatini]

On date Friday 2010-10-01 20:36:10 +0200, Michael Niedermayer encoded:
> On Fri, Oct 01, 2010 at 06:08:49PM +0200, Stefano Sabatini wrote:
> > ---
> >  libavutil/rational.c |    2 ++
> >  libavutil/rational.h |    2 ++
> >  2 files changed, 4 insertions(+), 0 deletions(-)
> > 
> > diff --git a/libavutil/rational.c b/libavutil/rational.c
> > index 0e0571e..b5af28e 100644
> > --- a/libavutil/rational.c
> > +++ b/libavutil/rational.c
> > @@ -98,6 +98,8 @@ AVRational av_d2q(double d, int max){
> >  #define LOG2  0.69314718055994530941723212145817656807550013436025
> >      int exponent= FFMAX( (int)(log(fabs(d) + 1e-20)/LOG2), 0);
> >      int64_t den= 1LL << (61 - exponent);
> > +    if (isinf(d))
> > +        return (AVRational){1,0};
> 
> if iam not mistaken then the int cast above has undefined behavior in this case

Why?

Note that one line below there is:
   if (isnan(d))
        return (AVRational){0,0};

Regards.
-- 
FFmpeg = Foolish Foolish Monstrous Ponderous Empowered Gargoyle