Re: [PATCH 0/6] Fix support for biarch compilers and cross cflags

[Matheus Kowalczuk Ferst]

On 21/06/2022 04:51, Paolo Bonzini wrote:
> This series fixes two bugs with configure's cross compilation detection:
> 
> - first, --cross-cflags is not obeyed by pc-bios/ compilation
> 
> - second, on a ppc64le machine, the host compiler can be used for ppc64
>    tests/tcg;

That may be true for the compiler, but the complete toolchain is usually 
single endian. For instance, Debian/Ubuntu, Fedora, and FreeBSD lack 
libc and crt*.o for the foreign endianness. So we'd be able to build 
ppc64-softmmu tests (which are not upstream yet) but not 
ppc64-linux-user in ppc64le hosts.

> however, this is not being done because $cpu does not
>    match the target.  Likewise, on an x86_64 machine the host compiler
>    can be used to build both i386 tests/tcg and pc-bios/optionrom, but
>    the special casing done by the configure script only covers the latter.
> 
> The two are related because, if only the first was fixed, pc-bios/optionrom
> would use either the i386 or the x86_64 cflags depending on which cross
> compiler was found.  So patches 2-4 tackle not just the cross CFLAGS
> problem with pc-bios, but also the biarch compiler problem with i386
> and ppc.  Patch 5 then covers the other biarch compilers.
> 
> The other two patches are just cleanups.
> 
> Supersedes: <20220607094031.1227714-1-pbonzini@redhat.com>
> 
> Paolo Bonzini (6):
>    pc-bios/optionrom: use -m16 unconditionally
>    configure, pc-bios/optionrom: pass cross CFLAGS correctly
>    configure, pc-bios/s390-ccw: pass cross CFLAGS correctly
>    configure, pc-bios/vof: pass cross CFLAGS correctly
>    configure: allow more host/target combos to use the host compiler
>    configure: write EXTRA_CFLAGS for all sub-Makefiles
> 
>   configure                     | 50 ++++++++++++++++++-----------------
>   pc-bios/optionrom/Makefile    | 15 +----------
>   pc-bios/optionrom/code16gcc.h |  3 ---
>   pc-bios/s390-ccw/Makefile     | 20 +++++++-------
>   pc-bios/s390-ccw/netboot.mak  |  6 ++---
>   pc-bios/vof/Makefile          |  8 +++---
>   6 files changed, 43 insertions(+), 59 deletions(-)
>   delete mode 100644 pc-bios/optionrom/code16gcc.h
> 
> --
> 2.36.1
> 
> 


Thanks,
Matheus K. Ferst
Instituto de Pesquisas ELDORADO <http://www.eldorado.org.br/>
Analista de Software
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