Updated referenced github actions. #151

	name: gcc linux

	on:
	push:
	pull_request:
	workflow_dispatch:

	env:
	TEST_DIR: ./tests


	jobs:
	all:
	strategy:
	fail-fast: false
	matrix:
	gcc_version: [9, 10]
	cpp_version: [c++17, c++20]
	arch: [m64, m32] # 64 and 32 bit
	buildmode: [~ , -O3 -DNDEBUG, -O3 -DNDEBUG -ffast-math]

	# gcc 9 does not support C++20
	exclude:
	- gcc_version: 9
	cpp_version: c++20

	runs-on: ubuntu-20.04
	timeout-minutes: 10

	steps:
	- uses: actions/checkout@v4

	- name: Install gcc-multilib for x86 if required
	# Creating a 32 bit executable on a 64 bit OS requires the gcc multilib.
	# It is not installed by default on the github runner.
	if: ${{ matrix.arch == 'm32' }}
	run: \|
	sudo apt update
	sudo apt install ${{ format('gcc-{0}-multilib g++-{0}-multilib', matrix.gcc_version) }} -y

	- name: Build and run tests
	working-directory: ${{env.TEST_DIR}}
	env:
	CXX: ${{ format('g++-{0}', matrix.gcc_version) }}
	ADDITIONAL_FLAGS: ${{ format('-{0} -std={1} {2}', matrix.arch, matrix.cpp_version, matrix.buildmode) }}
	run: make generic

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