#1069367 qemu: FTBFS on arm64: build-dependency not installable: gcc-powerpc64-linux-gnu

Package:
src:qemu
Source:
src:qemu
Submitter:
Lucas Nussbaum
Date:
2025-08-17 18:11:42 UTC
Severity:
normal
Tags:
#1069367#5
Date:
2024-04-20 12:11:37 UTC
From:
To:
Hi,

During a rebuild of all packages in sid, your package failed to build
on arm64.


Relevant part (hopefully):
The full build log is available from:
http://qa-logs.debian.net/2024/04/20/qemu_8.2.2+ds-2_unstable-arm64.log

All bugs filed during this archive rebuild are listed at:
https://bugs.debian.org/cgi-bin/pkgreport.cgi?tag=ftbfs-20240420;users=lucas@debian.org
or:
https://udd.debian.org/bugs/?release=na&merged=ign&fnewerval=7&flastmodval=7&fusertag=only&fusertagtag=ftbfs-20240420&fusertaguser=lucas@debian.org&allbugs=1&cseverity=1&ctags=1&caffected=1#results

A list of current common problems and possible solutions is available at
http://wiki.debian.org/qa.debian.org/FTBFS . You're welcome to contribute!

If you reassign this bug to another package, please mark it as 'affects'-ing
this package. See https://www.debian.org/Bugs/server-control#affects

If you fail to reproduce this, please provide a build log and diff it with mine
so that we can identify if something relevant changed in the meantime.

#1069367#10
Date:
2024-04-20 12:27:29 UTC
From:
To:
20.04.2024 15:11, Lucas Nussbaum wrote:

I don't understand what are you suggesting to do here.

Should I disable all foreign compilers and code in qemu?  This way,
qemu will be nearly useless.

Or should you perhaps file a bug against gcc to provide powerpc64 cross-compilers
for arm64?  If it's this variant, why are you filing this bug report against qemu?

Thanks,

/mjt

#1069367#19
Date:
2024-04-20 12:33:05 UTC
From:
To:
Hi Michael,

This is part of a mass rebuild, first building on arm64 and then on
armhf and armel. So I'm not suggesting anything. :-)

Is this failing because the build is trying to build arch:all packages,
that can only be built on amd64? If so, the bug severity could be
lowered, clearly.

Lucas

#1069367#24
Date:
2024-04-20 12:39:44 UTC
From:
To:
20.04.2024 15:33, Lucas Nussbaum wrote:
[..]

Aha.

Well.  Yes, this is exactly the case.  qemu uses quite a few cross-compilers to
build various firmware components.  This is arch-all package qemu-system-data.
Most of these cross-compilers are available on x86 _only_, including the
mentioned gcc-powerpc64-linux-gnu.

I especially made these deps to be in Build-Depends-Indep only, - to be able
to (re)build qemu on non-x86 by using `apt --arch-only`.

I can't say this is a bug to begin with, - wrt lowering its severity.  If it
is a bug, it's a bug in gcc, not qemu (since it is gcc which does not provide
these cross-compilers on all architectures).  Or in the build environment.

Thanks,

/mjt

#1069367#29
Date:
2024-04-20 13:28:18 UTC
From:
To:
Sure. The only reason for leaving a bug behind is that, if there had
been a "FTBFS everywhere except amd64 when building arch-indep
packages", I would have caught this and not filed this bug. wishlist +
wontfix would be OK.

Lucas

#1069367#44
Date:
2024-08-12 05:27:52 UTC
From:
To:
Why not submit a bug to src:gcc-14-cross.
It should be easy to add ppc64 target on host arm64.

#1069367#49
Date:
2024-08-12 05:49:50 UTC
From:
To:
12.08.2024 08:27, YunQiang Su wrote:

There's no requirement for arch-all packages to be buildable on
every architecture.  As long as arch-all is built on amd64, I
see no reason to submit bug reports.

Why arm64, why not all the rest?  Please keep in mind gcc is a
large thing and requires quite some resources to build, esp.
on slower architectures.  Basically, amd64 is the fastest we
have, which also happens to be the most widely used.  As long
as it works, I wont bother.

/mjt

#1069367#54
Date:
2024-08-12 07:27:48 UTC
From:
To:
Sure, while arm64 is powerful enough for it now ;)

Arm64 porters are working on trying to do such work.
They requested me to add arm64 support of src:gcc-N-cross-mipsen
years ago.

So, I guess that the arm64 porters may wish they have ppc64 cross toolchain.