Earlier framing was wrong — the wall isn't 'Arch ARM clang 22 vs Arch
x86_64 clang 23'. Arch x86_64 is also on 22.1.3; LLVM 23 isn't anywhere
in extra/staging. The flags chromium 147 emits come from chromium's
clang fork (Google maintains an LLVM fork with chromium-specific
passes), not upstream LLVM 23. PKGBUILD'ing clang 23 is the wrong tree.
Right tree: cross-compile from x86_64 so chromium's bundled clang
prebuilt is reachable. CIPD has full linux-amd64 prebuilts, gclient
sync works cleanly, no qemu-x86_64-static dance needed.
his provisioned CT 220 chromium-builder-x86 on data (Ryzen 7 1700,
14 cores, 32 GiB RAM, 200 GiB ZFS). data is normally asleep — woke
via /opt/herding/bin/wake-data. Reach pattern: hertz -> ssh data ->
pct exec 220.
Source fetch running as chromium-fetch.service transient unit on
CT 220. Once src is in, plan: tools/clang/scripts/update.py for
chromium's bundled clang + arm64 sysroot, gn gen with target_cpu=arm64,
build, transfer aarch64 binary to ohm/fresnel/ampere.
boltzmann chromium-builder LXD container preserved as fallback; can
be torn down if cross-compile pans out.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
First-build summary on chromium-builder@boltzmann. gn gen succeeds
with our V4L2VDA-unlock args. ninja fails immediately on:
1. chromium 147 emits clang flags (-fno-lifetime-dse,
-fsanitize-ignore-for-ubsan-feature=array-bounds) that clang 22
doesn't know. Arch Linux ARM is on clang 22; clang 23 hasn't
landed in extra yet.
2. Bundled x86_64 esbuild is invoked via qemu-x86_64-static but
/lib64/ld-linux-x86-64.so.2 isn't installed — same shape as the
bundled node-linux-x64 issue we already fixed by symlinking to
system node. Smaller wall.
Documents 5 paths forward (grind patches / pin chromium 132 (7Ji's
known-good) / pin 138-141 middle ground / use chromium's bundled
clang / wait for Arch ARM clang 23) with estimated effort and trade-
offs. Recommends pinning to a chromium version that compiles clean
against clang 22 as the fastest path to a working browser, then
bumping as Arch ARM bumps clang.
Build host state preserved — container running, source extracted,
gn-gen'd, no compile artifacts. Easy to resume from any of the five
paths.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
test0r