os: fix join_path and join_path_singe to respect absolute paths #16730

	name: sdl CI

	on:
	workflow_dispatch:
	push:
	paths:
	- 'vlib/**'
	- 'thirdparty/**'
	- 'cmd/tools/builders/**.v'
	- 'cmd/tools/vshader.v'
	- '**/sdl_ci.yml'
	- '!**.md'
	pull_request:
	paths:
	- 'vlib/**'
	- 'thirdparty/**'
	- 'cmd/tools/builders/**.v'
	- 'cmd/tools/vshader.v'
	- '**/sdl_ci.yml'
	- '!**.md'

	concurrency:
	group: ${{ github.workflow }}-${{ github.ref == 'refs/heads/master' && github.sha \|\| github.ref }}
	cancel-in-progress: true

	jobs:
	v-compiles-sdl-examples:
	runs-on: ubuntu-20.04
	timeout-minutes: 30
	env:
	VFLAGS: -cc tcc
	steps:
	- uses: actions/checkout@v4
	- name: Build V
	run: make && sudo ./v symlink

	- name: Install dependencies
	run: \|
	v retry 'sudo apt update'
	v retry 'sudo apt install -y libsdl2-dev libsdl2-ttf-dev'
	v retry 'sudo apt install -y libsdl2-mixer-dev libsdl2-image-dev'

	- name: Clone sdl into .vmodules
	run: \|
	v retry 'git clone --filter=blob:none https://github.com/vlang/sdl'
	cd sdl
	mkdir -p ~/.vmodules
	ln -s $(pwd) ~/.vmodules/sdl

	- name: Ensure SDL setup works
	run: ./v ~/.vmodules/sdl/setup.vsh

	- name: Run tests
	run: ./v test sdl

	- name: Build sdl shared
	run: ./v -shared -g sdl

	- name: Build sdl examples
	run: \|
	v shader sdl/examples/sdl_opengl_and_sokol
	v should-compile-all sdl/examples/
	~/.vmodules/sdl/examples/versions/main

	- name: Check SDL works, when installed through vpm
	run: \|
	rm -rf sdl/
	rm -rf ~/.vmodules/sdl
	v retry 'v install sdl'
	ls -la ~/.vmodules/sdl/
	v ~/.vmodules/sdl/setup.vsh
	v run ~/.vmodules/sdl/examples/versions

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