Add clang clangonmp compiling options to Makefile #4

	name: Continuous Integration

	on:
	push:
	branches:
	- master
	paths: ['.github/workflows/', '/Makefile', '*/.h', '*/.c']
	pull_request:
	types: [opened, synchronize, reopened]
	paths: ['/Makefile', '/.h', '/.c']

	env:
	BRANCH_NAME: ${{ github.head_ref \|\| github.ref_name }}

	jobs:
	# check basic builds to avoid breaking changes
	ubuntu-focal-make:
	runs-on: ubuntu-20.04

	steps:
	- name: Clone
	id: checkout
	uses: actions/checkout@v1

	- name: Dependencies
	id: depends
	run: \|
	sudo apt-get update
	sudo apt-get install build-essential -y

	- name: Build
	id: make_build
	run: \|
	make

	- name: Build runfast
	id: make_build_runfast
	run: \|
	make runfast

	macOS-latest-make:
	runs-on: macos-latest

	steps:
	- name: Clone
	id: checkout
	uses: actions/checkout@v1

	- name: Dependencies
	id: depends
	continue-on-error: true
	run: \|
	brew update

	- name: Build
	id: make_build
	run: \|
	make

	- name: Build runfast
	id: make_build_runfast
	run: \|
	make runfast

	- name: Build clang
	id: make_build_clang
	run: \|
	make clang

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