[FFmpeg-devel] [HOWTO] Building FFmpeg for iPhone

[Jason Millard]

>  You should add -arch armv7 to cflags and ldflags for 4a and -arch
>>> armv6 for 4b (the warning about -force_cpusubtype_ALL indicates that
>>> this will be required in the future.) This sets a specific cpu subtype
>>> for the mach-o file, which allows you lipo together binaries.
>>>
>>
>> I tried that, and got this error:
>>
>> cc1: error: unrecognized command line option "-arch"
>>
>> The warning is harmless, and only shows that Apple's compiler team are
>> a bunch of idiots, but we knew that already.
>>
>
> Oops, -arch is only recognized by "gcc" not "arm-apple-darwin9-gcc-4.2.1".
> So you'd need
> --cc=/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc
>
> The advantage of specifying it is that you can have a single binary that
> has full NEON opts, but still works on the older devices.


I've tried to compile using the gcc instead of arm-apple-darwin9-gcc-4.2.1
suggestion

   ./configure
--cc=/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc --as='
gas-preprocessor.pl/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc'
--sysroot=/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS3.1.sdk
--enable-cross-compile --target-os=darwin --arch=armv6 --cpu=arm1176jzf-s

and get

   /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc is unable to
create an executable file. C compiler test failed.

I tried with "gcc-4.2.1" with the same result. Is there something else I
should be doing?

-- Jason