added MinGW workflow #2

	name: CI-cygwin

	on: [push, pull_request]

	permissions:
	contents: read

	defaults:
	run:
	shell: cmd

	jobs:
	build:

	strategy:
	matrix:
	compiler: [g++]
	fail-fast: false

	runs-on: windows-2025

	env:
	CXX: ${{ matrix.compiler }}

	steps:
	- run: git config --global core.autocrlf input

	- uses: actions/checkout@v4
	with:
	persist-credentials: false

	- name: Set up Cygwin
	uses: cygwin/cygwin-install-action@master
	with:
	platform: 'x86_64'
	packages: \|
	gcc-g++
	python3
	cmake

	- name: make simplecpp
	run: make -j4 CXXOPTS="-Werror"

	- name: make test
	run: make -j4 test

	- name: selfcheck
	run: \|
	make -j4 selfcheck

	- name: Run CMake
	run: \|
	cmake -S . -B cmake.output -DCMAKE_COMPILE_WARNING_AS_ERROR=On

	- name: CMake simplecpp
	run: \|
	cmake --build cmake.output --target simplecpp -- -j 4

	- name: CMake testrunner
	run: \|
	cmake --build cmake.output --target testrunner -- -j 4

	- name: Run testrunner
	run: \|
	./cmake.output/testrunner

	- name: Run with libstdc++ debug mode
	if: matrix.compiler == 'g++'
	run: \|
	make clean
	make -j4 test selfcheck CXXOPTS="-Werror -g3 -D_GLIBCXX_DEBUG"

	- name: Run with libc++ hardening mode
	if: matrix.compiler == 'clang++' && matrix.msystem == 'CLANG64'
	run: \|
	make clean
	make -j4 test selfcheck CXXOPTS="-Werror -stdlib=libc++ -g3 -D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_DEBUG" LDOPTS="-lc++"

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