Re: Bug#939453: sbcl: Please pass host architecture explicitly when calling make.sh in debian/rules

Hi Sébastien!

On 9/14/19 4:43 PM, Sébastien Villemot wrote:
>> I was just trying to build sbcl for ppc64 on a powerpc Debian with a ppc64
>> chroot and noticed that the build set the compiler architecture to "ppc"
>> during build.
> 
> It looks like this particular case is somehow expected. See line 362 of
> make-config.sh: for a Debian architecture of "ppc64", the SBCL
> architecture is explicitly set at "ppc". However, for a Debian
> architecture of "ppc64el", then the SBCL architecture is "ppc64".

Yes, that's correct. On hppa, on the other hand, the problem is that
sbcl does not consider the case of a 32-bit userland on a 64-bit,
although this is currently the common use case for hppa.

> I don’t really understand why there is such a strange mapping, but at
> least your problem does not come from the Debian packaging.

The mapping exists because for architectures like PowerPC and SPARC it
used to be very common to use a 32-bit userland on a 64-bit kernel.

This way you would get the advantage to use large virtual address
spaces on the one hand and getting high performance due to the use
of 32-bit pointers on the other hand.

Unlike x86, both PowerPC and SPARC didn't make very big jumps from
32 to 64 bits unless the 32-bit baseline you started from was very
old which was not the case in Debian, for example.

In any case, it would be very useful if this mapping could be added
to debian/rules for at least hppa and ppc64.

ifeq (hppa,$(DEB_HOST_ARCH))
	export SBCL_ARCH=hppa
endif

ifeq (ppc64,$(DEB_HOST_ARCH))
	export SBCL_ARCH=ppc64
endif

Could you add this to debian/rules?

FWIW, for hppa, you can alternatively backport my patch which I contributed
upstream [1].

Thanks,
Adrian

> [1] https://github.com/sbcl/sbcl/commit/d78e5e730dd41c6db80c4f6604a9cb66f41171b3