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 1.2.0 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/1.2.0/ferrocene-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-unknown-linux-gnu.tar.gz",
    sha256 = "4082058e4d054b1e26261e7ec99f01bf807f87b4ea580d246e48d9ccd487a591",
    coverage_tools_url = "https://github.com/eclipse-score/ferrocene_toolchain_builder/releases/download/1.2.0/coverage-tools-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-unknown-linux-gnu.tar.gz",
    coverage_tools_sha256 = "5a136b0b654625b794aec9e189ab1be92a23c0a56eb6fc16984b629fee034cab",
    miri_sysroot_url = "https://github.com/eclipse-score/ferrocene_toolchain_builder/releases/download/1.2.0/miri-sysroot-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-unknown-linux-gnu.tar.gz",
    miri_sysroot_sha256 = "8b745cc64fe4d9d27081196cc565ea3cd198b24fce0ef7e2f014a11d85629745",
    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 1.2.0 artifacts:

Base URL: https://github.com/eclipse-score/ferrocene_toolchain_builder/releases/download/1.2.0/

File	sha256
ferrocene-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-aarch64-unknown-nto-qnx800.tar.gz	d5ccceb0e3118a5e6bfdf1a3f894054db3c2cd346f927b39a57a69faf688849d
ferrocene-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-aarch64-unknown-linux-gnu.tar.gz	3fd5fe5da4836eb6d554731e7899d378a6992106ce6275b136279dec29598383
ferrocene-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-unknown-linux-gnu.tar.gz	4082058e4d054b1e26261e7ec99f01bf807f87b4ea580d246e48d9ccd487a591
ferrocene-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-pc-nto-qnx800.tar.gz	3fede22a89d7431668d4bc2810147a957d2b334ee8cb7097ad9c56b546f805cc
coverage-tools-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-unknown-linux-gnu.tar.gz	5a136b0b654625b794aec9e189ab1be92a23c0a56eb6fc16984b629fee034cab
miri-sysroot-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-unknown-linux-gnu.tar.gz	8b745cc64fe4d9d27081196cc565ea3cd198b24fce0ef7e2f014a11d85629745
miri-sysroot-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-aarch64-unknown-linux-gnu.tar.gz	74f90eabcb34809e44300535016f25eb0cf4a500763c0d18e7f587583b5b9908
miri-sysroot-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-x86_64-pc-nto-qnx800.tar.gz	ac434b7dc3cc3d67d31f73513a027aea50cca355c189c3a3f8c3162b1fccbca0
miri-sysroot-779fbed05ae9e9fe2a04137929d99cc9b3d516fd-aarch64-unknown-nto-qnx800.tar.gz	8fc8f406c33a7dc31362133b8a2ffbb66b44f62354bfc98a3bc21a1fcbc9a7e6

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