readme: add musl libc support and update OpenBSD and FreeBSD #4211

	name: Coverage

	on:
	push:
	branches:
	- main
	pull_request:
	branches:
	- main

	jobs:
	coverage:
	runs-on: ubuntu-latest

	env:
	CMAKE_GENERATOR: Ninja

	steps:
	- uses: actions/checkout@v4

	- name: fix flaky azure mirrors
	if: ${{ runner.os == 'Linux' }}
	run: \|
	sudo sed -i 's/azure\./de\./' /etc/apt/sources.list

	- name: install packages
	run: \|
	sudo apt-get update && sudo apt-get install -y ninja-build

	- name: make
	run: \|
	cmake -B build -DCMAKE_C_FLAGS="--coverage" -DCMAKE_EXE_LINKER_FLAGS="--coverage" -DUSE_TRACE=ON
	cmake --build build -j -t retest

	- name: retest
	run: \|
	./build/test/retest -a -v
	./build/test/retest -r -m select -v

	- name: gcov
	run: \|
	gcov build/*/.o

	- name: install gcovr
	run: \|
	pip install gcovr==5.0

	- name: coverage check
	run: \|
	min_cov="64.4"
	cov=$(~/.local/bin/gcovr -r . -s \| grep lines \| awk '{ print $2 }' \| sed 's/%//')
	echo "Coverage: ${cov}% (min $min_cov%)"
	exit $(echo "$cov < $min_cov" \| bc -l)

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