Link linux builds with lld (bfd rejects --start-lib on 20.04) - #6
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The bfd linker on ubuntu:20.04 (binutils 2.34) rejects the --start-lib flag Bazel emits: /usr/bin/ld.bfd: unrecognized option '--start-lib' --start-lib is only supported by gold and lld. Install lld and link both linux arches with --linkopt=-fuse-ld=lld: it handles --start-lib and also sidesteps the aarch64 gold erratum-843419 crash, so one uniform linker works for x86_64 and arm64. Linker choice does not affect glibc symbol versioning, so portability is unchanged. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Follow-up to #5. The containerized linux build got further — the glibc-2.31 container is correct and darwin built fine — but both linux legs failed at link:
Cause
PR #5 forced
--linkopt=-fuse-ld=bfd, but Bazel emits--start-lib/--end-lib, which only gold and lld support —bfddidn't gain--start-libuntil binutils 2.38, and ubuntu:20.04 ships 2.34.Fix
Install
lldand link both linux arches with--linkopt=-fuse-ld=lld. lld:--start-lib(unlike 20.04's bfd), anderratum-843419crash that bit us back in Release workflow: auto-derive version + fix linux-arm64 linker #2,so one uniform linker works for x86_64 and arm64. Linker choice doesn't change which glibc/libstdc++ symbol versions are referenced, so the glibc 2.31 portability from #5 is preserved.
Validation status (build pipeline, run 28060201258)
Head SHA
477ccdfe72— confirm before merging.🤖 Generated with Claude Code