[MPlayer-dev-eng] [FFmpeg-devel] [PATCH] remove useless math.h include in libavutil/mathematics.h

[Guillaume POIRIER]

Hello,

On Mon, Aug 25, 2008 at 8:47 PM, David Conrad <lessen42 at gmail.com> wrote:
> On Aug 25, 2008, at 12:07 PM, Måns Rullgård wrote:
>
>> Reimar Döffinger <Reimar.Doeffinger at stud.uni-karlsruhe.de> writes:
>>
>>> On Mon, Aug 25, 2008 at 05:47:49PM +0200, Guillaume Poirier wrote:
>>>>
>>>> I noticed that the include of math.h in libavutil/mathematics.h doesn't
>>>> seem to be usefull.
>>>
>>> The point is that it can provide M_E etc. If you remove it and some code
>>> (possibly indirectly) includes <math.h> after mathematics.h those will
>>> be defined twice. I.e. removing it IMHO makes a mess.
>>
>> Yes, the #include stays.
>>
>>>> In file included from /usr/include/math.h:26,
>>>>              from ./libavutil/mathematics.h:25,
>>>>              from ./libavutil/avutil.h:57,
>>>>              from liba52/parse.c:40:
>>>> /usr/include/architecture/ppc/math.h:179: error: parse error before
>>>> '__attribute__'
>>>
>>> Well, wtf is in math.h that it stumbles over?
>>
>> This is getting better and better.  First macosx can't link with its
>> own libs, and now it can't even compile its own headers.  If this
>> keeps up, it won't be long before it stops booting at all, and we'll
>> finally see an end to these problems.
>
> It uses __attribute__((always_inline)), and mplayer's liba52/bitstream.h
> defines  always_inline to __attribute__((always_inline)) inline, so it's
> expanded to __attribute__((__attribute__((always_inline)) inline)) and
> pukes.
>
> Attached mplayer patch should fix the root of the problem. (untested)

Good catch.
This simpler change:

Index: liba52/parse.c
===================================================================
--- liba52/parse.c	(revision 27478)
+++ liba52/parse.c	(working copy)
@@ -32,12 +32,12 @@
 #include <string.h>
 #include <inttypes.h>

+#include "libavutil/avutil.h"
 #include "a52.h"
 #include "a52_internal.h"
 #include "bitstream.h"
 #include "tables.h"
 #include "mm_accel.h"
-#include "libavutil/avutil.h"

 #ifdef HAVE_MEMALIGN
 /* some systems have memalign() but no declaration for it */


did the trick as well.
Reimar, what do you think about that change?


BTW, here's an example of what part of math.h clashes:

                static __inline__ int __inline_isfinitef        (float
     ) __MATH_H_ALWAYS_INLINE__;
                static __inline__ int __inline_isfinited
(double     ) __MATH_H_ALWAYS_INLINE__;
                static __inline__ int __inline_isfinite         (long
double) __MATH_H_ALWAYS_INLINE__;
                static __inline__ int __inline_isinff           (float
     ) __MATH_H_ALWAYS_INLINE__;
                static __inline__ int __inline_isinfd
(double     ) __MATH_H_ALWAYS_INLINE__;
                static __inline__ int __inline_isinf            (long
double) __MATH_H_ALWAYS_INLINE__;
                static __inline__ int __inline_isnanf           (float
     ) __MATH_H_ALWAYS_INLINE__;
                static __inline__ int __inline_isnand
(double     ) __MATH_H_ALWAYS_INLINE__;
                static __inline__ int __inline_isnan            (long
double) __MATH_H_ALWAYS_INLINE__;


Guillaume
-- 
One should not give up hope on imbeciles. With a little training, you
can make them into soldiers.
 -- Pierre Desproges