ci(cppcheck-all, cppcheck-differential): add cppcheck #6

	name: cppcheck-differential

	on:
	pull_request:

	jobs:
	cppcheck-differential:
	runs-on: ubuntu-latest

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

	- name: Install dependencies
	run: \|
	sudo apt-get update
	sudo apt-get install -y build-essential cmake git libpcre3-dev

	- name: Install Cppcheck from source
	run: \|
	git clone https://github.com/danmar/cppcheck.git
	cd cppcheck
	git checkout 2.14.1
	mkdir build
	cd build
	cmake ..
	make -j $(nproc)
	sudo make install

	- name: Get changed files
	id: changed-files
	run: \|
	git fetch origin ${{ github.base_ref }} --depth=1
	git diff --name-only FETCH_HEAD ${{ github.sha }} > changed_files.txt
	cat changed_files.txt

	- name: Run Cppcheck on all files
	run: \|
	cppcheck --enable=all --inconclusive --check-level=exhaustive --xml . 2> cppcheck-report.xml
	shell: bash

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