Add cross-compilation example for STM32F303 #5

	---
	name: STM32F303 Cross-Compilation

	on:
	push:
	branches: [ "main" ]
	paths:
	- 'Cargo.toml'
	- 'Cargo.lock'
	- 'build.rs'
	- 'src/**'
	- 'xbuild-tests/**'
	- '.github/workflows/rust.yml'
	pull_request:
	branches: [ "main" ]
	paths:
	- 'Cargo.toml'
	- 'Cargo.lock'
	- 'build.rs'
	- 'src/**'
	- 'xbuild-tests/**'
	- '.github/workflows/rust.yml'

	env:
	CARGO_TERM_COLOR: always

	jobs:
	lint:
	name: Lint
	runs-on: ubuntu-latest
	defaults:
	run:
	working-directory: xbuild-tests/stm32
	steps:
	- name: Install Rust toolchain
	uses: actions-rs/toolchain@v1
	with:
	toolchain: stable
	components: rust-src
	target: thumbv7em-none-eabihf
	- uses: actions/checkout@v4
	- name: Check format
	run: cargo fmt --check
	- name: Check
	run: cargo check
	- name: Clippy
	run: cargo clippy

	build-float:
	needs: lint
	name: Build and Test (floating-point)
	runs-on: ubuntu-latest
	defaults:
	run:
	working-directory: xbuild-tests/stm32
	steps:
	- name: Install Rust toolchain
	uses: actions-rs/toolchain@v1
	with:
	toolchain: stable
	components: rust-src
	target: thumbv7em-none-eabihf
	- uses: actions/checkout@v4
	- name: Build
	run: cargo build --no-default-features --features=kalman-float

	build-fixed:
	needs: lint
	name: Build and Test (fixed-point)
	runs-on: ubuntu-latest
	defaults:
	run:
	working-directory: xbuild-tests/stm32
	steps:
	- name: Install Rust toolchain
	uses: actions-rs/toolchain@v1
	with:
	toolchain: stable
	components: rust-src
	target: thumbv7em-none-eabihf
	- uses: actions/checkout@v4
	- name: Build
	run: cargo build --no-default-features --features=kalman-fixed

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