[Libav-user] Fwd: Re: FFmpeg vp8 decoding: cross compile on Windows for ARM target

[Carl Eugen Hoyos]

2018-08-02 14:21 GMT+02:00, ed mcmurray <emcmurray at aevee.com>:
> On 8/2/2018 8:18AM, Ed McMurray wrote:
>
> On 8/1/2018 5:38 PM, Carl Eugen Hoyos wrote:
>> 2018-07-29 16:20 GMT+02:00, ed mcmurray <emcmurray at aevee.com>:
>>> I have tried the Window pathname suggestions, with no real success. I've
>>> decided to eliminate this as a variable, so I have switched to try to
>>> build FFmpeg libs under Linux(Ubuntu 17.10).  This is the exact process
>>> that I have followed so far:
>>> *
>>> *1: I have downloaded and decompressed ffmpeg v4.0.2 into ffmpeg source
>>> root directory.
>>> 2: I have downloaded and installed Pre-buil2 GNU toolchain forArm
>>> Cortex-M for Linux (gcc-arm-none-eabi-7-2018-q2 update-linux)
>>>       from Arm website:
>>> https://developer.arm.com/open-source/gnu-toolchain/gnu-rm
>>> 3: from cli, I set working directory to ffmpeg source root directory.  (
>>> I created a simple helloworld.c program in working directory, to test
>>> compiler)
>>> 4: from cli,  I verified arm compiler did successfully create expected
>>> object file for helloworld.c test.
>>> 5: from cli, I ran cofigure shell script:
>>> $ ./configure --enable-cross-compile
>>> --cc=/home/ed/Project/armCrossCompile gcc-arm-none-eabi-eabi-gcc
>>> --target-os=none arch=arm
>> (There is something wrong with the "arch" option, both here and in the
>> log.)
>>
>> Should probably be:
>> ./configure --cross-prefix=/home/ed/Project/armCrossCompile
>> gcc-arm-none-eabi-eabi-
>> --target-os=none --arch=arm
> I've run configure exactly as shown above. The results were the same as
> previous run.
>   I've attached config.log file.
>>> 6: This is the returned error message:
>>> /home/ed/Project/armCrossCompile/gcc-arm-none-eabi-7-2018-q2-update/bin/arm-none-eabi-gcc
>>>
>>> is unable to create an executable file. C compiler test failed.
>>>
>>> I have attached zipped log file to show any possible clues.  I won't be
>>> able to do too much more today.  I will start Monday morning trying to
>>> understand what the log file is showing and what I might be missing.
>>> Again, any advice is appreciated.
>> Please do not compress the log, please avoid top-posting here.
>>
>> If it still fails, try to compile FFmpeg's test program ("int
>> main(void){ return 0; }")
>> with the options FFmpeg uses ("-march=armv4t") and find out if it
>> really succeeds
>> from cli.
> I wasn't exactly sure I understood this step. So I created a simple C
> test file with
> int main(void) { return 0; }
>
> I then ran cross compiler from cli with the FFmpeg option:
> $
> /home/ed/Project/armCrossCompile/gcc-arm-none-eabi-7-2018-q2-update/bin/arm-none-eabi-gcc
>
> -c -march=armv4t test.c

You also have to test without "-c" to (likely) see the same error as
configure.

Please set your mailer to text-only, Carl Eugen