Is casting a negative integer to unsigned defined behavior?
On Wed, Jul 18, 2018 at 3:55 AM Michael Niedermayer <mich...@niedermayer.cc> wrote: > On Tue, Jul 17, 2018 at 02:37:55PM -0700, Fredrik Hubinette wrote: > > > > > utils.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > e69f1a3a447e331cad7ea85e28c0ed13e48ce33c > 0001-Avoid-undefined-behavior-when-start_time_text-is-1-6.patch > > From d7bd55c3d280c10b990577003a985296f10a2b59 Mon Sep 17 00:00:00 2001 > > From: Fredrik Hubinette <hu...@google.com> > > Date: Tue, 17 Jul 2018 14:35:55 -0700 > > Subject: [PATCH] Avoid undefined behavior when start_time_text is -1<<63 > > > > --- > > libavformat/utils.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/libavformat/utils.c b/libavformat/utils.c > > index c9cdd2b470..5b83ed7872 100644 > > --- a/libavformat/utils.c > > +++ b/libavformat/utils.c > > @@ -2666,7 +2666,7 @@ static void update_stream_timings(AVFormatContext > *ic) > > duration = FFMAX(duration, duration1); > > } > > } > > - if (start_time == INT64_MAX || (start_time > start_time_text && > start_time - start_time_text < AV_TIME_BASE)) > > + if (start_time == INT64_MAX || (start_time > start_time_text && > start_time - AV_TIME_BASE < start_time_text )) > > Casting to uint64_t should be a more complete fix. > > [...] > > -- > Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB > > Awnsering whenever a program halts or runs forever is > On a turing machine, in general impossible (turings halting problem). > On any real computer, always possible as a real computer has a finite > number > of states N, and will either halt in less than N cycles or never halt. > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel > _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
