[FFmpeg-cvslog] r14484 - in trunk/libavcodec: audioconvert.c audioconvert.h

[Diego Biurrun]

On Sun, Aug 03, 2008 at 01:17:06PM +0200, Michael Niedermayer wrote:
> .On Sat, Aug 02, 2008 at 07:00:02PM +0200, Diego Biurrun wrote:
> > On Sat, Aug 02, 2008 at 06:47:06PM +0200, Michael Niedermayer wrote:
> > > On Sat, Aug 02, 2008 at 06:46:08PM +0200, Diego Biurrun wrote:
> > > > On Sat, Aug 02, 2008 at 06:32:36PM +0200, Michael Niedermayer wrote:
> > > > > On Sat, Aug 02, 2008 at 06:15:20PM +0200, Diego Biurrun wrote:
> > > > > > On Sat, Aug 02, 2008 at 05:54:56PM +0200, Michael Niedermayer wrote:
> > > > > > > On Sat, Aug 02, 2008 at 06:40:13PM +0300, Uoti Urpala wrote:
> > > > > > > > On Sat, 2008-08-02 at 17:23 +0200, Michael Niedermayer wrote:
> > > > > > > > > On Sat, Aug 02, 2008 at 02:50:40PM +0200, Diego Biurrun wrote:
> > > > > > > > > > On Sat, Aug 02, 2008 at 04:25:52AM +0200, Michael Niedermayer wrote:
> > > > > > > > > > > it also uses lrintf & snprintf thus also needs one way or another
> > > > > > > > > > > stdio.h and math.h with  _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE defined before
> > > > > > > > > > > inclusion of math.h
> > > > > > > > 
> > > > > > > > Those are standard C, so any special defines are only required if the
> > > > > > > > default is to use old versions.
> > > > > > > 
> > > > > > > no
> > > > > > > -------
> > > > > > > Linux Programmer?s Manual                                                             LRINT(3)
> > > > > > > 
> > > > > > > NAME
> > > > > > >        lrint, lrintf, lrintl, llrint, llrintf, llrintl - round to nearest integer
> > > > > > > 
> > > > > > > SYNOPSIS
> > > > > > > [...]
> > > > > > >        Link with -lm.
> > > > > > > 
> > > > > > >    Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
> > > > > > > 
> > > > > > >        All functions shown above: _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE; or cc -std=c99
> > > > > > >        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> > > > > > > -------
> > > > > > > > > > These definitions are part of the global CFLAGS, no need to duplicate
> > > > > > > > > > them.
> > > > > > > > > 
> > > > > > > > > until it causes you an hour of work when you try to compile it
> > > > > > > > > in mplayer that happenes not to set them.
> > > > > > > > 
> > > > > > > > MPlayer uses -std=gnu99 with GCC, so no extra defines are needed for
> > > > > > > > standard C functions. So even if such defines are not set any problems
> > > > > > > > could only occur if you're using some compiler which MPlayer does not
> > > > > > > > recognize and which does not support C99 functions by default.
> > > > > > > 
> > > > > > > see above, the manual page of lrintf explain it rather clearly, what is
> > > > > > > needed on linux. I do not know if you propose to drop linux support or
> > > > > > > if you propose to depend on undocumented options.
> > > > > > 
> > > > > > -std=gnu99 is a superset of -std=c99, so no problem.
> > > > > 
> > > > > The manual disagrees with you, it lists _XOPEN_SOURCE, _ISOC99_SOURCE and 
> > > > > -std=c99 it does not list gnu99
> > > > 
> > > > You are reading the wrong manual.  The gcc manual clearly states that
> > > > gnu99 is a superset of c99.
> > > 
> > > gcc is a c library?
> > 
> > I have no idea what silly game you are trying to play here, but you
> > quoted above (linebreak mine):
> > 
> >   All functions shown above: _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE;
> >   or cc -std=c99
> >      ^^^^^^^^^^^
> > 
> > Since -std=gnu99 is a superset of -std=c99, we are safe.
> 
>     tcc gnu99test.c -o gnu99test -std=gnu99
> tcc: invalid option -- '-std=gnu99'

Does tcc understand -std=c99?

> now, i know you will tell me that you check for gnu99 support in mplayer
> and omit "-std=gnu99" if the compiler fails to compile with it.

Yes, of course the option is checked for, though only in the gcc case.

What exactly was the point you were trying to make here?

> But when you omit it, it no longer is a superset of c99 and you no longer
> follow the libc docs requirement of _ISOC99_SOURCE || _XOPEN_SOURCE >= 600
> of course compilers might enable these defines by default but thats a gamble.

Support for other compilers in MPlayer is embryonic at best and the
whole compiler option handling in MPlayer's configure is in for an
overhaul...

Diego