[FFmpeg-devel] [PATCH] swscale: add workaround for building 32 bit shared libs with gcc4.2 on 64 bit Mac OS X

[Michael Bradshaw]

On Sat, Jun 2, 2012 at 8:42 AM, Michael Niedermayer <michaelni at gmx.at> wrote:
> On Fri, Jun 01, 2012 at 02:15:53PM -0600, Michael Bradshaw wrote:
>> Hi,
>>
>> Attached patch allows shared 32 bit ffmpeg to be built with gcc4.2 on
>> 64 bit Mac OS X. Without this, --disable-asm must be passed to
>> configure.
>>
>> I expect this patch will be a bit controversial, and if anyone has a
>> better solution I'd be happy to see it.
>>
>> See discussion here:
>> http://ffmpeg.org/pipermail/ffmpeg-user/2012-May/006851.html (and
>> continued here:
>> http://ffmpeg.org/pipermail/ffmpeg-user/2012-June/006854.html) for
>> more information relating to this.
>
> does replacing some of the problemtic "m" cases by MANGLE() work ?

I'm not exactly sure what the "m" cases are, but I took a shot in the
dark and tried:

@@ -884,7 +884,7 @@ static inline void RENAME(rgb15tobgr24)(const
uint8_t *src, uint8_t *dst, int sr
             "por        %%mm5, %%mm3    \n\t"

             :"=m"(*d)
-            :"m"(*s),"m"(mask15b),"m"(mask15g),"m"(mask15r),"m"(mmx_null),"m"(mul15_mid),"m"(mul15_hi)
+            :"m"(*s),""(MANGLE(mask15b)),""(MANGLE(mask15g)),""(MANGLE(mask15r)),""(MANGLE(mmx_null)),""(MANGLE(mul15_mid)),""(MANGLE(mul15_hi))
             :"memory");
         /* borrowed 32 to 24 */
         __asm__ volatile(


Which just resulted in:

libswscale/x86/rgb2rgb_template.c: In function ‘rgb15tobgr24_MMX’:
libswscale/x86/rgb2rgb_template.c:825: warning: asm operand 2 probably
doesn’t match constraints
libswscale/x86/rgb2rgb_template.c:825: warning: asm operand 3 probably
doesn’t match constraints
libswscale/x86/rgb2rgb_template.c:825: warning: asm operand 4 probably
doesn’t match constraints
libswscale/x86/rgb2rgb_template.c:825: warning: asm operand 5 probably
doesn’t match constraints
libswscale/x86/rgb2rgb_template.c:825: warning: asm operand 6 probably
doesn’t match constraints
libswscale/x86/rgb2rgb_template.c:825: warning: asm operand 7 probably
doesn’t match constraints
libswscale/x86/rgb2rgb_template.c:825: error: impossible constraint in ‘asm’


That's probably not what you meant to try though. If not, I'm going to
need your help in understanding what to try...

Thanks,

Michael