[FFmpeg-devel] [PATCH 2/3] lavfi/psnr: rename pow2 to pow_2

Ronald S. Bultje rsbultje at gmail.com
Mon Mar 27 01:17:57 EEST 2017


Hi,

On Sun, Mar 26, 2017 at 5:35 PM, Clément Bœsch <u at pkh.me> wrote:

> On Sun, Mar 26, 2017 at 05:21:23PM -0400, Ronald S. Bultje wrote:
> > Hi,
> >
> > On Sun, Mar 26, 2017 at 2:53 PM, Clément Bœsch <u at pkh.me> wrote:
> >
> > > This conflict with the DJGPP libc which includes a pow2 function¹
> > >
> > > We can not make DJGPP posix only to avoid the conflict due to the lack
> > > of posix_memalign.
> > >
> > > [1]: http://www.delorie.com/djgpp/doc/libc-2.02/libc_536.html
> > > ---
> > >  libavfilter/vf_psnr.c | 8 ++++----
> > >  1 file changed, 4 insertions(+), 4 deletions(-)
> > >
> >
> > Patch is OK. I have no idea what the second line (body) of the commit
> > message means.
> >
>
> I'll improve the message, but basically the djgpp libc can be configured
> to be POSIX only, where these functions functions and macro (pow2, PI) are
> not defined. We could do that in the configure (-D_POSIX_SOURCE).
>
> Unfortunately, DJGPP does not have posix_memalign(), and will lack its own
> memalign function we use in lavu/mem.c if we use -D_POSIX_SOURCE. (we
> could use the recently defunct memalign hack, but better use the proper
> allocation function).


I'm not sure I understand. The user might have installed djgpp instead of
libc. But we have no influence whatsoever over how the user compiled djgpp,
so FFmpeg should work with as well as without a posix-compiled djgpp, right?

Ronald


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