No description
Mathieu Benoit
a42e43bcf1
Built at stage 1, failed at stage 2, in gold:
<artificial>:(.text+0xc44e): undefined reference to
`void gold::gold_error_at_location<32, true>(...)'
`<artificial>` and the .ltrans object names are LTO's, and it does not come from
makepkg -- the chroot carries !lto with an empty LTOFLAGS. It comes from the
PKGBUILD: --enable-pgo-build=lto. gold's explicitly-instantiated templates do
not survive it here. Stage 1 got away with it because the host's GCC did the
work; stage 2 uses ours, at -O2 -march=z13 where stage 1 passed no flags.
PGO and LTO are build-time optimisations: what changes is how long binutils
takes to compile and how fast the linker runs, not what it can do. The
alternatives were removing gold, a linker Arch ships, or debugging LTO template
instantiation in a linker upstream has deprecated.
The first attempt at this hook looked for --with-build-config=bootstrap-lto,
which is in gcc's PKGBUILD, not binutils'. Its own assertion caught it.
--- FR ---
Bâti à l'étage 1, échoué à l'étage 2, dans gold :
<artificial>:(.text+0xc44e): undefined reference to
`void gold::gold_error_at_location<32, true>(...)'
`<artificial>` et les noms d'objets .ltrans sont ceux du LTO, et il ne vient pas
de makepkg — le chroot porte !lto avec un LTOFLAGS vide. Il vient du PKGBUILD :
--enable-pgo-build=lto. Les gabarits explicitement instanciés de gold n'y
survivent pas. L'étage 1 s'en tirait car le GCC de l'hôte faisait le travail ;
l'étage 2 utilise le nôtre, à -O2 -march=z13 là où l'étage 1 ne passait rien.
PGO et LTO sont des optimisations de construction : ce qui change, c'est la durée
de compilation et la vitesse du lieur, pas ce qu'il sait faire. Les options
étaient de retirer gold, un lieur qu'Arch livre, ou de déboguer une instanciation
de gabarit sous LTO dans un lieur abandonné en amont.
La première version de ce hook cherchait --with-build-config=bootstrap-lto, qui
est dans le PKGBUILD de gcc, pas de binutils. Sa propre assertion l'a arrêtée.
Assisted-by: Claude Opus 5
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| .github/workflows | ||
| arch-kernel | ||
| boot | ||
| patches | ||
| scripts | ||
| .env.example | ||
| .gitignore | ||
| CODEOWNERS | ||
| Containerfile | ||
| LICENSE | ||
| Makefile | ||
| README.md | ||
| TODO.md | ||
Arch Linux s390x
A port of Arch Linux to IBM s390x mainframe architecture with systemd support.
Boots a full Arch Linux system on IBM mainframes (or QEMU s390x emulation) using a hybrid build: cross-compilation for the kernel, native s390x compilation on z/VM for userspace.
Quick Start
make container # build dev container (first time)
cp .env.example .env # configure z/VM access
make all # build kernel + initramfs + systemd
make test-systemd # boot it
What Works
- Arch Linux kernel 6.18.6-arch1 with Arch patches, cross-compiled
- Initramfs via modified mkinitcpio
- Static busybox built natively on z/VM, 2.3MB
- Root filesystem with ext4, switch_root to real rootfs
- Systemd as PID 1
Pacman, bash, and GNU coreutils are not yet ported.
Build System
The build uses two tiers:
Cross-compilation (x86_64 host): Kernel is built in a Fedora 43 container with s390x-linux-gnu-gcc. Initramfs is generated with a patched mkinitcpio that handles cross-architecture binary injection.
Native compilation (s390x z/VM): Busybox and systemd must be built on real s390x hardware. The z/VM system runs RHEL 9.6 with GCC 11.5.0. Scripts handle SSH deployment and retrieval automatically via .env configuration.