Refine the build instructions for backends #275

	name: CI

	on: [push, pull_request]

	jobs:
	detect-code-related-file-changes:
	runs-on: ubuntu-24.04
	outputs:
	has_code_related_changes: ${{ steps.set_has_code_related_changes.outputs.has_code_related_changes }}
	steps:
	- name: Check out the repository
	uses: actions/checkout@v4
	- name: Test changed files
	id: changed-files
	uses: tj-actions/changed-files@v45
	with:
	files: \|
	.ci/**
	mk/**
	include/**
	src/**
	backend/**
	apps/**
	tools/**
	.clang-format
	Makefile
	- name: Set has_code_related_changes
	id: set_has_code_related_changes
	run: \|
	if [[ ${{ steps.changed-files.outputs.any_changed }} == true ]]; then
	echo "has_code_related_changes=true" >> $GITHUB_OUTPUT
	else
	echo "has_code_related_changes=false" >> $GITHUB_OUTPUT
	fi

	host-x64:
	needs: [detect-code-related-file-changes]
	if: needs.detect-code-related-file-changes.outputs.has_code_related_changes == 'true'
	runs-on: ubuntu-24.04
	steps:
	- uses: actions/checkout@v4
	- name: install-dependencies
	run: \|
	sudo apt-get update -q -y
	sudo apt install libsdl2-dev libjpeg-dev libpng-dev
	shell: bash
	- name: default build
	run: \|
	tools/kconfig/defconfig.py --kconfig configs/Kconfig configs/defconfig
	tools/kconfig/genconfig.py configs/Kconfig
	make

	coding-style:
	needs: [detect-code-related-file-changes]
	if: needs.detect-code-related-file-changes.outputs.has_code_related_changes == 'true'
	runs-on: ubuntu-24.04
	steps:
	- uses: actions/checkout@v4
	- name: coding convention
	run: \|
	sudo apt-get install -q -y clang-format-18
	.ci/check-newline.sh
	.ci/check-format.sh
	shell: bash

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