Bump actions/checkout from 2 to 4 #52

	name: CI

	on:
	push:
	branches: [ main, staging, trying ]
	pull_request:

	jobs:
	build:
	runs-on: ubuntu-latest
	timeout-minutes: 30
	continue-on-error: ${{ matrix.rust_version == 'nightly' }}

	strategy:
	matrix:
	include:
	- rust_version: stable
	target: thumbv7em-none-eabi
	rustflags: --deny warnings
	- rust_version: stable
	target: thumbv7em-none-eabihf
	rustflags: --deny warnings
	- rust_version: stable
	target: thumbv8m.main-none-eabi
	rustflags: --deny warnings
	- rust_version: beta
	target: thumbv7em-none-eabihf
	- rust_version: nightly
	target: thumbv7em-none-eabihf

	steps:
	- uses: actions/checkout@v4
	- name: Install Rust
	run: \|
	rustup install --profile=minimal ${{ matrix.rust_version }}
	rustup target add ${{ matrix.target }}
	- name: Build
	run: cargo build --target ${{ matrix.target }}
	env:
	RUSTFLAGS: ${{ matrix.rustflags }}

	example:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Install Rust
	run: rustup target add thumbv7em-none-eabi
	- name: Build example
	run: cd example && cargo build

	fmt:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Install Rust stable
	run: \|
	rustup install --profile=minimal stable
	rustup component add rustfmt
	- name: Check fmt
	run: cargo fmt -- --check

	ci:
	if: ${{ success() }}
	# all new jobs must be added to this list
	needs: [build, fmt]
	runs-on: ubuntu-latest
	steps:
	- name: CI succeeded
	run: exit 0

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