Re: Patch for config.guess for "cross-compiling" x86_64 -> powerpc on Mac OS X <= 10.6

[Mojca Miklavec]

Hi,

I've got quite some criticism and some approvals, but no answer from
the maintainer yet. So: is there any chance to accept the patch?

Having the proper behaviour of config.guess is pretty important for me
and the projects where I would need this would probably refuse to
include random patches for config.guess that don't make it upstream.

Thank you very much,
    Mojca


On 19 April 2017 at 03:52, Bruno Haible wrote:
> The patch looks good to me:
>
>   - I confirm that executables built on Mac OS X 10.5.8 (Darwin 9.8.0)
>     with "gcc -arch ppc" are of type 'Mach-O executable ppc' and
>     are directly executable on x86_64 Mac OS X 10.5.8.
>
>   - This is a vendor-provided feature; I have this feature on x86_64
>     Mac OS X 10.5.8 although I haven't installed or configured or
>     enabled anything special.
>
>   - On a PowerPC Mac OS X 10.5.8 the result of config.guess is
>     powerpc-apple-darwin9.8.0, and the patch makes it return the same
>     triple for CC="gcc -arch ppc" on x86_64 Mac OS X 10.5.8.
>
>   - The patch is complete: When you compile with "gcc -arch ppc64" you
>     get executables of type 'Mach-O 64-bit executable ppc64' but such
>     files are not directly executable on x86_64 Mac OS X 10.5.8:
>       $ ./a.out
>       -bash: ./a.out: Bad CPU type in executable
>
>> The main problem is that config.guess is being used by various
>> software packages to answer two completely different questions and the
>> answer might not always be the same:
>>
>> (1) Which platform am I building for?
>> (2) Which platform am I running on / which binaries should I download?
>
> config.guess is the answer for (1). That's why it uses $CC_FOR_BUILD.
> For (2) there is no simple answer on bi-arch systems.
>
> Bruno
>