build: byte-identical CI/local builds via --remap-path-prefix; toolchain 1.91.1#18
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…91.1 CI and local produced different binaries (and thus a different measured linux.efi / PCR). Root cause: rustc embeds dependency source paths, and CI runs with CARGO_HOME=/tmp/.cargo (the Makefile's CI cache redirect) while local uses /src/.cargo, so the two bake different absolute registry paths into every binary that has path-embedding deps. stage2 matched only because the leaf pulls none. Fix: --remap-path-prefix in the per-target rustflags rewrites both /src/.cargo and /tmp/.cargo to a fixed /cargo, so the build no longer depends on where CARGO_HOME is. Verified: after the remap the stage1 binary contains only /cargo/registry paths (0 /src, 0 /tmp) and is bit-deterministic. (trim-paths would be cleaner but is still nightly-only on 1.91.) Also bump rust-toolchain 1.91.0 -> 1.91.1 to match stage0: the toolchain file was left at .0 since the v0.1.0 tag while stage0 moved to .1, and two repos that must produce byte-compatible framing should share a compiler (std/sysroot paths are toolchain-version-specific). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
…alyzer The CARGO_HOME remap left one divergence: when rust-src is installed (rust- analyzer does this in the local shared rustup; CI's fresh toolchain has not), rustc emits std panic-location paths from the sysroot (/src/.rustup/toolchains/<tc>/lib/rustlib/src/rust/...) instead of the baked /rustc/<hash> that CI produces. Remap that sysroot path to the same /rustc/<hash> so the two converge. Verified: local now builds linux.efi / stage2 / stage1 byte-identical to the CI-built artifacts (4b6aa700 / 0eb6f0e7 / 1a0d586a). The remap is a no-op in CI (no rust-src there), so CI output is unchanged. The hash is toolchain-specific; update it when bumping the toolchain (a stale value silently no-ops, which the CI==local check catches). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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What
Make CI and local builds bit-identical so the measured
linux.efi(and its PCR) reproduces independently.Why
CI builds with
CARGO_HOME=/tmp/.cargo(the Makefile CI cache redirect) while local uses/src/.cargo. rustc embeds dependency source paths, so the two baked different absolute registry paths into every binary with path-embedding deps -> differentstage1/linux.efi. (stage2matched only because the leaf has no such deps.)Fix
--remap-path-prefix=/src/.cargo=/cargo+=/tmp/.cargo=/cargoin both musl targets' rustflags -> the build no longer depends on whereCARGO_HOMEis. Verified locally:stage1now contains only/cargo/registrypaths (0/src, 0/tmp) and is bit-deterministic. (trim-pathswould be cleaner but is nightly-only on 1.91.)rust-toolchain.toml1.91.0 -> 1.91.1 to match stage0 (drifted since the v0.1.0 tag; std/sysroot paths are toolchain-version-specific).Verification
This PR's CI run builds the artifacts; comparing them to a local build with the same config is the acceptance test (
linux.efi/stage2should match byte-for-byte). Local reference (x86_64):linux.efi 65c9fdbf,stage2 72978d6f.🤖 Generated with Claude Code