Add a few intrinsics contracts #30

	# This workflow is responsible for building the standard library using the bootstrap script
	# and executing the Rust regression.

	name: Rust Tests
	on:
	workflow_dispatch:
	pull_request:
	branches: [ main ]
	push:
	paths:
	- 'library/**'
	- 'rust-toolchain.toml'
	- '.github/workflows/rustc.yml'

	defaults:
	run:
	shell: bash

	jobs:
	build:
	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	# Note windows-latest is currently failing.
	os: [ubuntu-latest, macos-latest]
	steps:
	- name: Checkout Library
	uses: actions/checkout@v4
	with:
	path: head

	- name: Checkout `upstream/master`
	uses: actions/checkout@v4
	with:
	repository: rust-lang/rust
	path: upstream
	fetch-depth: 0
	submodules: true

	# Run rustc twice in case the toolchain needs to be installed.
	# Retrieve the commit id from the `rustc --version`. Output looks like:
	# `rustc 1.80.0-nightly (84b40fc90 2024-05-27)`
	- name: Checkout matching commit
	run: \|
	cd head
	rustc --version
	COMMIT_ID=$(rustc --version \| sed -e "s/.($.$ .*/\1/")
	cd ../upstream
	git checkout ${COMMIT_ID}

	- name: Copy Library
	run: \|
	rm -rf upstream/library
	cp -r head/library upstream

	- name: Run tests
	working-directory: upstream
	env:
	# Avoid error due to unexpected `cfg`.
	RUSTFLAGS: "--check-cfg cfg(kani) --check-cfg cfg(feature,values(any()))"
	run: \|
	./configure --set=llvm.download-ci-llvm=true
	./x test --stage 0 library/std

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