[WIP] Add cmake build scheme #5215

	name: Header checks

	on:
	pull_request:
	branches: [ develop, master ]
	push:
	branches: [ develop, master ]
	paths-ignore:
	- 'doygen/**'
	- 'hooks/**'
	- 'licenses/**'
	- 'LICENSE.md'
	- 'README.md'
	- 'RELEASE-NOTES.txt'

	permissions:
	contents: read

	concurrency:
	group: ${{ github.workflow }}-${{ github.head_ref \|\| github.run_id }}
	cancel-in-progress: true

	jobs:
	windows:
	name: Windows
	runs-on: windows-latest

	steps:
	- uses: actions/checkout@v4
	- uses: actions/setup-python@v5
	with:
	python-version: '3.x'

	- name: Print g++/mingw32-make version and path
	run: \|
	g++ --version
	Get-Command g++ \| Select-Object -ExpandProperty Definition
	mingw32-make --version
	Get-Command mingw32-make \| Select-Object -ExpandProperty Definition
	shell: powershell

	# - name: Build Math libs
	# shell: powershell
	# run: mingw32-make -f make/standalone math-libs -j2

	- name: Run header tests
	shell: powershell
	run: \|
	cmake -S . -B build -DCMAKE_BUILD_TYPE=RELEASE -DSTAN_TEST_HEADERS=ON
	cd build
	make -j2 test-headers

	opencl:
	name: OpenCL
	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v4

	- name: Run header tests
	run: \|
	cmake -S . -B build -DCMAKE_BUILD_TYPE=RELEASE -DSTAN_TEST_HEADERS=ON
	cd build
	make -j2 test-headers
	no_range_checks:
	name: NoRange
	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v4

	- name: Run header tests
	run: \|
	cmake -S . -B build -DCMAKE_BUILD_TYPE=RELEASE -DSTAN_NO_RANGE_CHECKS=ON
	cd build
	make -j4 test_unit_math_prim_err_subtests
	cd test
	ctest -R "unit_math_prim_err"

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