toolchains_rust

Bazel module that packages prebuilt Ferrocene Rust toolchains and a helper extension to wrap custom Ferrocene archives.

What’s inside

• MODULE.bazel: pins Ferrocene 1.3.1 archives built from the Ubuntu 24.04 Ferrocene image and depends on score_bazel_platforms.
• extensions/ferrocene_toolchain_ext.bzl: bzlmod extension to wrap arbitrary Ferrocene archives.
• Optional Ferrocene Rust coverage tools (symbol-report, blanket) when configured.
• Optional Miri toolchain support backed by prebuilt Miri sysroot archives.
• toolchains/ferrocene/BUILD.bazel: aliases to the preconfigured toolchains declared in MODULE.bazel.

Note: This module no longer ships platform definitions or the old rust sysroot extension. Consumers must provide rules_rust themselves.

Using the preconfigured Ferrocene toolchains (recommended)

bazel_dep(name = "rules_rust", version = "0.56.0")  # or your pinned version
bazel_dep(name = "score_toolchains_rust", version = "0.3.0", dev_dependency = True)

register_toolchains(
    "@score_toolchains_rust//toolchains/ferrocene:all",
    dev_dependency = True,
)

Preconfigured toolchains:

• ferrocene_x86_64_unknown_linux_gnu
• ferrocene_aarch64_unknown_linux_gnu
• ferrocene_x86_64_pc_nto_qnx800
• ferrocene_aarch64_unknown_nto_qnx800

Preconfigured Miri toolchain aliases:

• ferrocene_x86_64_unknown_linux_gnu_miri
• ferrocene_aarch64_unknown_linux_gnu_miri
• ferrocene_x86_64_pc_nto_qnx800_miri
• ferrocene_aarch64_unknown_nto_qnx800_miri

Preconfigured direct-Miri artifact aliases:

• *_miri_driver
• *_miri_sysroot_files
• *_miri_runtime_files

Coverage tools are available from the generated repositories (wrappers set LD_LIBRARY_PATH automatically):

bazel run @score_toolchains_rust//toolchains/ferrocene:ferrocene_x86_64_unknown_linux_gnu_symbol-report -- --help
bazel run @score_toolchains_rust//toolchains/ferrocene:ferrocene_x86_64_unknown_linux_gnu_blanket -- --help

Wrapping your own Ferrocene archives

bazel_dep(name = "rules_rust", version = "0.56.0")
bazel_dep(name = "score_toolchains_rust", version = "0.5.0")

ferrocene = use_extension(
    "@score_toolchains_rust//extensions:ferrocene_toolchain_ext.bzl",
    "ferrocene_toolchain_ext",
)

ferrocene.toolchain(
    name = "ferrocene_x86_64_unknown_linux_gnu",
    url = "https://github.com/eclipse-score/ferrocene_toolchain_builder/releases/download/1.3.1/ferrocene-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-unknown-linux-gnu.tar.gz",
    sha256 = "6fd7c7053a80463b2bfd24202de02e16959b18ed185c55b738148e9caac42eff",
    coverage_tools_url = "https://github.com/eclipse-score/ferrocene_toolchain_builder/releases/download/1.3.1/coverage-tools-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-unknown-linux-gnu.tar.gz",
    coverage_tools_sha256 = "9cf5d76b2e505bf2a8b2b47c60f191ac1273f87851ed387e53080b8e5d14dedf",
    miri_sysroot_url = "https://github.com/eclipse-score/ferrocene_toolchain_builder/releases/download/1.3.1/miri-sysroot-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-unknown-linux-gnu.tar.gz",
    miri_sysroot_sha256 = "143260fe3873249160d57b370717005828e129d3b6782448a32d8cc578384fe0",
    miri_sysroot_strip_prefix = "x86_64-unknown-linux-gnu",
    target_triple = "x86_64-unknown-linux-gnu",
    exec_triple = "x86_64-unknown-linux-gnu",
)

use_repo(ferrocene, "ferrocene_x86_64_unknown_linux_gnu")
register_toolchains("@ferrocene_x86_64_unknown_linux_gnu//:rust_ferrocene_toolchain")

miri_sysroot_url is the supported path for Miri integration. The generated repo expects a prebuilt Miri sysroot archive and does not build one at repository rule time. For the built-in Ferrocene toolchains, score_toolchains_rust re-exports a rules_rust Miri toolchain through the same simple public aliases:

build:x86_64-linux --extra_toolchains=@score_toolchains_rust//toolchains/ferrocene:ferrocene_x86_64_unknown_linux_gnu_miri

The base Ferrocene repos remain backward compatible because they only expose the direct miri wrapper and its artifacts. The rules_rust Miri toolchain is created in separate companion repositories and is only loaded when a *_miri alias is actually used. This keeps repositories that do not use Miri working with older rules_rust versions.

For custom Ferrocene archives, you can still opt in explicitly to the companion rules_rust Miri toolchain via ferrocene_rules_rust_miri_toolchain_ext.

Add more ferrocene.toolchain(...) entries for other archives such as aarch64-unknown-linux-gnu, aarch64-unknown-nto-qnx800, or x86_64-pc-nto-qnx800.

Ferrocene 1.3.1 artifacts:

Base URL: https://github.com/eclipse-score/ferrocene_toolchain_builder/releases/download/1.3.1/

File	sha256
ferrocene-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-aarch64-unknown-nto-qnx800.tar.gz	a8e80da21c6abebfb31063f3815cd3a4bbb5a1466855a12043d7c243ef152715
ferrocene-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-aarch64-unknown-linux-gnu.tar.gz	06ee88a935083068325b69028e9d4e9adc696542cea9b4322642a55dafcae552
ferrocene-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-unknown-linux-gnu.tar.gz	6fd7c7053a80463b2bfd24202de02e16959b18ed185c55b738148e9caac42eff
ferrocene-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-pc-nto-qnx800.tar.gz	655ad0d212baf63f4dd03065735ca55cddadc86cf6bd005aeb19689e348a0023
coverage-tools-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-unknown-linux-gnu.tar.gz	9cf5d76b2e505bf2a8b2b47c60f191ac1273f87851ed387e53080b8e5d14dedf
miri-sysroot-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-unknown-linux-gnu.tar.gz	143260fe3873249160d57b370717005828e129d3b6782448a32d8cc578384fe0
miri-sysroot-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-aarch64-unknown-linux-gnu.tar.gz	4059e74c79147b942eb595c14a5f998ebdb1063764ea756b4f32c21bf5903a16
miri-sysroot-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-pc-nto-qnx800.tar.gz	9684ea089c883a0739f402165fc6aa374a69641e763957c314688779e8124931
miri-sysroot-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-aarch64-unknown-nto-qnx800.tar.gz	3077170b7384d6bcf2cf8f53db8b670d48fc7e2237285b4fd799c64e7412bdff

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