README: add a general section on upstream toolchain support #13

	name: CI autotools

	on:
	push:
	pull_request:

	defaults:
	run:
	shell: bash

	jobs:
	build-and-test:
	name: ${{ matrix.name }}
	runs-on: ${{ matrix.os }}

	strategy:
	# When set to true, GitHub cancels
	# all in-progress jobs if any matrix job fails.
	fail-fast: false

	matrix:

	include:
	- name: linux-gcc
	os: ubuntu-latest

	steps:
	- name: Checkout Code
	uses: actions/checkout@v2

	- name: Setup apt cache
	uses: actions/cache@v2
	with:
	path: /var/cache/apt
	key: ${{ runner.os }}-apt-cache-${{ matrix.os }}-${{ github.sha }}
	restore-keys: \|
	${{ runner.os }}-apt-cache-${{ matrix.os }}-
	${{ runner.os }}-apt-cache-

	- name: Setup Common Prerequisites
	run: \|
	case ${{ runner.os }} in
	Linux*)
	sudo apt update
	# basic build depends:
	sudo apt install binutils-dev libelf-dev libiberty-dev libncurses-dev
	# dev-only depends:
	sudo apt install autoconf autoconf-archive automake flex bison gperf pkg-config
	# dist depends:
	sudo apt install lzip xz-utils
	;;
	esac

	- name: Generate ./configure
	run: ./autogen.sh

	- name: Configure
	run: ./configure --prefix=$PWD/install

	- name: Build
	run: make -j$(nproc)

	- name: Install
	run: make -j$(nproc) install

	- name: Distcheck
	run: make -j$(nproc) distcheck

	- name: Clean
	run: make -j$(nproc) distclean

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