David Tolnay

This commit performs a **dependency rename** within the **Buck2 build system**, specifically updating references to the `rand` crate. The `rand` dependency is consistently renamed to `rand_09` across various `BUCK` files, including those for `buck2_client_ctx`, `buck2_core`, `buck2_daemon`, and `starlark`. This **maintenance** task ensures proper and unambiguous dependency resolution for a specific version of the `rand` crate, preventing potential conflicts and preparing for future dependency management without altering any runtime functionality.

This commit performs a **build system maintenance** task by **renaming a dependency** within the **Folly Rust `tdigest` library's BUCK build configuration**. Specifically, the `rand` 0.9.2 dependency is now explicitly referred to as `rand_09` in the `folly/rust/tdigest/BUCK` file. This change helps to clarify dependency naming and prevent potential conflicts with other versions of the `rand` crate, ensuring the correct library is linked during compilation of the `tdigest` component.

This commit **updates the `clap` dependency** from version `4.5.60` to `4.6.0`. This **minor version bump** brings the project up-to-date with the latest features, improvements, and bug fixes available in the `clap` command-line argument parsing library. As an **automated, semver-compatible update**, this **maintenance task** ensures the project leverages the most recent stable enhancements without introducing breaking changes. This keeps the project's dependency on `clap` current and robust.

This commit **fixes build failures** for **Rust build scripts** that compile C/C++ code by ensuring necessary preprocessor flags are passed to the compiler shim. Previously, critical include paths like `-isystem` and `-resource-dir`, often specified in `CxxToolchainInfo`'s `preprocessor_flags`, were omitted, leading to "file not found" errors for standard library headers. The change in `_cargo_buildscript_impl` within `prelude/rust/cargo_buildscript.bzl` now correctly propagates these flags, enabling **successful compilation** of C/C++ dependencies. This **enhances the robustness** of the build system for Rust projects integrating with C/C++ toolchains.

This commit performs a **dependency update**, upgrading the `tempfile` library from version `3.26.0` to `3.27.0`. This **maintenance** task incorporates the latest minor version improvements and bug fixes from the upstream `tempfile` project. The change ensures that all components relying on temporary file creation and management benefit from enhanced stability and new features, without introducing breaking changes due to its semver-compatible nature.

This commit **addresses `dead_code` lint warnings** found within the **Rust components** of the `fbcode/folly` library. It performs a **code quality improvement** by either removing unused code or marking it appropriately to suppress the `dead_code` lint. This **maintenance task** ensures a cleaner codebase, reduces build noise, and improves overall maintainability for the **Folly Rust modules** without introducing any functional changes or regressions.

This commit **updates the Rust dependency versions** for the **`pyrefly`** project by regenerating its `Cargo.lock` file. This **maintenance update** ensures that the `fbcode/pyrefly/Cargo.lock` correctly reflects the dependencies for version **0.58.0**, which was inadvertently omitted in a prior version bump. It brings the `pyrefly` module's Rust ecosystem up to date, leveraging the latest compatible libraries and maintaining dependency consistency.

This commit performs a **maintenance update** by upgrading the project's **Rust toolchain** to `nightly-2026-01-18`. This change ensures that all development and CI/CD processes, including GitHub Actions, utilize the specified newer Rust nightly version. Consequently, the **documentation** in `HACKING.md` and `docs/getting_started/install.md` has been updated to reflect this new recommended toolchain. This update provides consistent guidance for developers and keeps the project current with the latest Rust developments.

This commit performs a **maintenance update** by upgrading the **Rust toolchain version** used throughout the project. It updates the global `rust-toolchain.toml` file and the `pyrefly/rust-toolchain` configuration to specify the new Rust nightly version. Consequently, all **GitHub Actions workflows** that rely on Rust, specifically `issue_ranking.yml`, `mypy_primer.yml`, and `pyrefly.yml`, are updated to utilize this newer toolchain. This ensures that all Rust-based builds and tests, both in CI/CD and local development, leverage the **latest specified Rust nightly features and fixes**.

This commit performs a **version update** for the `home` component, upgrading it from version `0.5.11` to `0.5.12`. This **maintenance** task ensures that the project benefits from the latest bug fixes and minor enhancements introduced in the newer `home` release. The update primarily affects the **dependency management** of the project, ensuring compatibility and stability with the updated component.

Update jobserver from 0.1.33 to 0.1.34

This commit **reverts** the previous change `D97513002`, which had suppressed unstable target features specifically for the `platform010-aarch64` architecture. By undoing that modification, this **maintenance** commit effectively **re-enables** the use of these unstable features for `platform010-aarch64` targets. This **corrective action** restores the prior build configuration, potentially impacting the compilation and runtime characteristics of code targeting `platform010-aarch64`.

This commit **updates** the project's **third-party dependency** on the `uuid` library, incrementing its version from 1.21.0 to **1.22.0**. This is a **semver-compatible version bump**, indicating that it should not introduce breaking changes but rather incorporates the latest features, performance improvements, and bug fixes from the upstream `uuid` package. The change primarily affects the **dependency management** of the project, ensuring it remains current with its external libraries. This is a routine **maintenance** task to keep the project's dependencies up-to-date.

Bump uuid 1.21.0 -> 1.22.0

This commit implements a **bug fix** by **disabling sanitizers** for C/C++ compilers that are invoked by **Rust build scripts**. Previously, specific **ARVR build modes** experienced critical linking errors due to an incompatible mix of sanitized and unsanitized object files, leading to undefined symbol issues. By modifying `prelude/rust/cargo_buildscript.bzl` to explicitly prevent sanitizer instrumentation in these build script compilers, this change **resolves build failures** and ensures successful compilation and linking. This prevents the problematic combination of sanitizer states, thereby stabilizing the build process for affected **ARVR targets**.

This commit introduces a **new capability** to the **Rust build system**, enabling **Cargo build scripts** to correctly access C/C++ compilers by **configuring environment variables** like `$LD`, `$CC`, `$CXX`, and `$AR`. It resolves issues where the `cc` crate failed to locate necessary tools by deriving compiler paths from `CxxToolchainInfo`. This enhancement allows build scripts to perform tasks requiring a C compiler, such as generating `config.h` or running `bindgen`, without requiring manual pre-generation or platform-specific workarounds. A new utility, `from_any_dir.py`, is also added to wrap compiler commands, ensuring they function correctly when invoked from arbitrary directories by build scripts.

This commit **fixes a bug** in the **Rust toolchain integration** by correctly handling `ResolvedStringWithMacros` objects when processing `rustc_flags` within `cargo_buildscript.bzl`. Previously, defining `rustc_flags` using `attrs.arg()` would cause an error because the implementation expected a string and attempted to call `startswith` on the `ResolvedStringWithMacros` object. This **enhancement** now **enables interpolation support for `rustc_flags`**, allowing for more dynamic and flexible toolchain configurations. Additionally, the logic for setting `OPT_LEVEL` is refined to only apply when the optimization level is numeric.

Unpatch cc crate by updating to 1.2.57

Patch cc with archiver command line length fix

This commit introduces a **new capability** to the **Rust build system**, specifically enhancing the `cargo_buildscript.bzl` module. It now automatically provides the `OPT_LEVEL` environment variable to **Cargo build scripts**, ensuring it accurately reflects the optimization level used for the main Rust compilation. This change allows build scripts to correctly adapt their behavior based on the current optimization settings, improving the fidelity and consistency of the build environment for Rust projects. The `_cargo_buildscript_impl` function is updated to facilitate this automatic environment variable propagation.