[Ffmpeg-devel] SVN 6723 of ffmpeg segfaults :(

[Rich Felker]

On Tue, Oct 17, 2006 at 09:24:03PM +0200, Michael Niedermayer wrote:
> Hi
> 
> On Tue, Oct 17, 2006 at 09:51:41PM +0300, Ismail Donmez wrote:
> > 17 Eki 2006 Sal 21:39 tarihinde, Tanim Islam ??unlar?? yazm????t??: 
> > > Hi:
> > >
> > > I have compiled ffmpeg on Ubuntu 5.10, using gcc (GCC) 4.0.3 20051121
> > > (prerelease) (Ubuntu 4.0.2-4ubuntu3). I compile with the following flags:
> > >
> > > --enable-mp3lame --enable-libogg --enable-vorbis --enable-faad
> > > --enable-faac --enable-xvid --enable-x264 --enable-a52 --disable-static
> > > --enable-shared --enable-gpl --enable-dts --prefix=$(HOME)/apps
> > > --disable-strip
> > > --enable-pthreads --disable-ffserver --enable-libgsm
> > >
> > > I run the following command:
> > >
> > > ffmpeg -i file.flv -vcodec mpeg4 -b 512 -acodec mp3 -ar 44100 -ac 2 -ab 64
> > > -y file.avi
> > >
> > > The program segfaults. Here is 1) the backtrace:
> > >
> > > (gdb) bt
> > > #0  0x0804cf83 in parse_arg_file (filename=0xbf86d364 "file.avi")
> > >     at ffmpeg.c:3200
> > 
> > That line has some interesting piece of code:
> > 
> > if(d==d && (opt->flags&AV_OPT_FLAG_ENCODING_PARAM))
> >    ^^^^
> > 
> > Someone tried to do if (1 && ... ) ?
> 
> NAN != NAN
> 
> if replacing the code above by !isnan(d) fixes the issue then you may
> submit a patch ...

Notice that the crash had nothing to do with the isnan... It happens
when testing the flag, indicating that opt is probably an invalid
pointer...

Rich