Experimental Rust on Linux/Alpha

This snapshot builds Rust with rustc_codegen_gcc and GCC/libgccjit, both as an x86_64-hosted cross-toolchain and as a native Alpha toolchain. The native compiler, Cargo, standard library, GCC and binutils have been installed on an AlphaServer ES40 running Gentoo. This is a personal proof of concept, not supported Rust or Gentoo Alpha support and not an upstream submission. It contains LLM-generated implementation and supporting material.

Current results

• Rust 1.102.0-dev, Cargo 1.101.0, GCC 17 development and upstream binutils 2.47.50.20261111; target alphaev6-unknown-linux-gnu (EV6 or newer).
• Alpha C ABI classification, inline assembly, target layout and libc bindings support std; additional changes cover metadata, bootstrap and support crates.
• Native C, C++ exception handling and Cargo/Rust compilation passed on the ES40. The Rust program exercised threads, atomics and UTF-8 file I/O.
• ripgrep 15.2.0, fd 10.5.0 and zoxide 0.10.0 are installed through Portage and passed functional checks on the actual machine.
• Native application source builds through Portage passed under QEMU. The physical ES40 zoxide source rebuild is in progress; that result is not yet claimed as a pass.

See installation results, test evidence, and the native toolchain record. Earlier cross-build results are in the historical overview.

Sources

The publication branch is alpha-experimental-20261111 in each repository:

Repository	Purpose
rust_alpha_stuff	Patches, probes, provenance, build scripts and Gentoo overlay
rust	Native Rust target/std/bootstrap snapshot, including its in-tree GCC backend
rustc_codegen_gcc	Standalone backend used for the cross-build checkpoint
gcc	Alpha JIT assembler relocation-sequence fix and regression test

Exact source revisions distinguish upstream bases from the experimental commits. The Rust fork includes its own in-tree backend; the standalone backend branch is not interchangeable with that subtree. There are no local binutils source changes in this snapshot. Existing upstream Alpha fixes are used rather than copied into a local binutils patch set.

The libc and other dependency changes are supplied as patches in the baseline patch set and the native additions. Cargo's prepared lockfile is in experimental/20261111/native-toolchain/locks.

Trying the native toolchain

Read the Gentoo installation guide first. It explains the required archives, checksums, overlay registration and source-build command. The repository contains source and configuration, not compiler binaries. The installer needs four prepared distfiles; do not assume a Git clone alone is sufficient. The accompanying install kit is prepared separately for release.

With the native toolchain installed, use:

/opt/rust-alpha-experimental/bin/cargo-alpha new --vcs none hello-alpha
cd hello-alpha
/opt/rust-alpha-experimental/bin/cargo-alpha run

The wrapper selects GCC, libgccjit and the patched support crates. It does not replace the system compiler. Unused-patch warnings are expected when a project does not depend on those support crates.

For rebuilding the supported Gentoo package, as root:

FEATURES="${FEATURES} test" emerge --ask --oneshot --usepkg=n app-shells/zoxide::rust-alpha

Portage integration boundaries

dev-lang/rust-alpha-bin owns /opt/rust-alpha-experimental. The adapted application ebuilds inherit alpha-cargo.eclass, depend on that compiler, and select its cargo-alpha wrapper. Vendored dependencies allow offline builds. Per-package keywords and exact-version unmask entries enable only our packages.

This is not a virtual/rust provider and is not registered with eselect rust or Gentoo's general slotted rust.eclass. Arbitrary unmodified Rust ebuilds do not automatically work. Full integration needs compiler-slot packaging and selection, component/feature compatibility, and more package tests. The current package does not provide rustdoc, clippy or rustfmt.

Limits and reproduction

Rust panics abort; Rust unwinding and doctests are unsupported. Executables use non-PIE defaults while the loader/linker issue is investigated. LTO and incremental compilation are disabled in the tested configuration. Rust C-variadic function definitions and reliable f128 are unavailable. Passing these probes is not a full compiler correctness claim or a native self-bootstrap.

Build scripts and configurations record the actual builds. They expect the prepared workspace and Alpha sysroot; archived TOML files contain the original absolute paths. They are not yet an empty-machine bootstrap installer. The source snapshots and patches support inspection and reproducing the experiment with those prerequisites.

For upstream discussions, authors should write their own account of the work and follow each project's contribution policies. These experimental branches are not requests for upstream maintainers to review or accept generated code.