build: byte-identical CI/local builds via --remap-path-prefix#9
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CI and local produced different measured binaries (stage0.efi and thus PCR4/14). 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, baking different absolute registry paths into the binary. Fix: --remap-path-prefix in every artifact-producing target's rustflags (musl x2, uefi x2) 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 stage0.efi contains only /cargo/registry paths (0 /src, 0 /tmp). trim-paths would be cleaner but is still nightly-only on 1.91. 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 instead of the baked /rustc/<hash> that CI produces. Remap that sysroot path to the same /rustc/<hash> on every artifact target so the two converge. Verified: local stage0.efi is now fully path-canonical (0 /src/.cargo, 0 /src/.rustup; only /cargo + /rustc), matching CI's build. The remap is a no-op in CI (no rust-src there). The hash is toolchain-specific; update it when bumping the toolchain (a stale value silently no-ops, which CI==local 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
stage0.efi(PCR4/14) reproduces independently.Why
CI builds with
CARGO_HOME=/tmp/.cargowhile local uses/src/.cargo; rustc embeds dependency source paths, so each baked different absolute registry paths intostage0.efi.Fix
--remap-path-prefix=/src/.cargo=/cargo+=/tmp/.cargo=/cargoin every artifact-producing target (musl x2, uefi x2) -> build isCARGO_HOME-independent. Verified locally:stage0.eficontains only/cargo/registrypaths (0/src, 0/tmp). (trim-pathswould be cleaner but is nightly-only on 1.91.)Verification
This PR's CI run builds the db-signed
BOOTX64.EFI; grepping it should show only/cargopaths (no/tmp//src), provingCARGO_HOME-independence. Local reference (x86_64):stage0.efi 433bea84,ena.efi e4957fe6.Pairs with lockboot/stage1's reproducibility PR.
🤖 Generated with Claude Code