A Rust Standard Library implementation for FreeRTOS

This is a work-in-progress fork of the Rust Standard Library targeting FreeRTOS. So far, it has basic support of threads and sync primitives.

Features

• stdout via semi-hosting
• Support for panic abort and panic unwind

Supported targets / platforms

• thumbv7m-none-eabi tested on Qemu's mps2-an385

Used Rust toolchain version

std library is tightly coupled with the Rust compiler, and it uses many internal features. Therefore a nightly toolchain must be used. Moreover, a specific nightly has to be used, the one that matches whenever last this library was updated from the upstream std library. This version is tracked in [supported-toolchain.txt]

How to use

It is recommended to include this repo as a submodule in your workspace, this is because the FreeRTOS build system needs to include c files from it.

$ git submodule add [email protected]:sheref-sidarous/freertos-std.git

rust app:

• Add freertos-std dependency as the std library in Cargo.toml

std = {path = "../freertos-std", package = "freertos-std"}

Where path refers to where freertos-std were checked out. Use features panic-unwind and stdio-semihosting if you want to.

• Build your app as a staticlib

[lib]
crate-type = ["staticlib"]

FreeRTOS build system:

• Build the C file src/sys/freertos/rust_std_shim.c from freertos-std within your FreeRTOS the build system
• Link the Rust app built as a static library

Panic Unwind

This library supports panic unwind, but to use it you'd need to recompile Rust toolchain to support unwind for your selected target. There is a helper script in freertos-std-example subfolder rust-unwind-toolchain for an example of doing so. Then in your rust app, enable freertos-std panic-unwind feature and add the compiler flag -Cpanic=unwind

rustflags = ["-Cpanic=unwind"]

Example usage

Check out freertos-std-example for an example that builds and runs this library using Qemu