build-windows-gcc.yml

name: Bundle portable Windows gcc (MinGW-w64)

on:
  workflow_dispatch:

permissions:
  contents: write

jobs:
  bundle:
    runs-on: windows-latest
    steps:
      - uses: actions/checkout@v4

      - name: Download WinLibs portable gcc
        shell: powershell
        run: |
          $url = "https://github.com/brechtsanders/winlibs_mingw/releases/download/14.2.0posix-19.1.1-12.0.0-ucrt-r2/winlibs-x86_64-posix-seh-gcc-14.2.0-mingw-w64ucrt-12.0.0-r2.zip"
          Write-Host "Downloading WinLibs gcc..."
          Invoke-WebRequest -Uri $url -OutFile gcc.zip -UseBasicParsing
          Write-Host "Extracting..."
          Expand-Archive gcc.zip -DestinationPath gcc_extracted

      - name: Extract minimal toolchain
        shell: powershell
        run: |
          # We only need the compiler and its immediate runtime deps.
          # Full mingw64 is ~700MB -- extract just what's needed to compile.
          $src = "gcc_extracted\mingw64"
          $dst = "libs\windows-x64\gcc"
          New-Item -ItemType Directory -Force -Path $dst

          # Essential compiler binaries
          $bins = @("g++.exe", "gcc.exe", "as.exe", "ld.exe", "windres.exe",
                    "cpp.exe", "cc1.exe", "cc1plus.exe", "collect2.exe",
                    "libgcc_s_seh-1.dll", "libstdc++-6.dll", "libwinpthread-1.dll",
                    "libgomp-1.dll")
          foreach ($b in $bins) {
            $f = Get-ChildItem -Path $src -Recurse -Filter $b -ErrorAction SilentlyContinue | Select-Object -First 1
            if ($f) { Copy-Item $f.FullName -Destination $dst; Write-Host "Copied $b" }
          }

          # Runtime libraries needed by compiled sketches
          Copy-Item "$src\bin\libgcc_s_seh-1.dll" $dst -ErrorAction SilentlyContinue
          Copy-Item "$src\bin\libstdc++-6.dll" $dst -ErrorAction SilentlyContinue
          Copy-Item "$src\bin\libwinpthread-1.dll" $dst -ErrorAction SilentlyContinue

          # Include dirs (needed at compile time)
          Copy-Item "$src\include" "$dst\include" -Recurse -Force
          Copy-Item "$src\lib\gcc" "$dst\lib\gcc" -Recurse -Force
          Copy-Item "$src\lib\libstdc++*" "$dst\lib\" -Force -ErrorAction SilentlyContinue
          Copy-Item "$src\lib\libgcc*" "$dst\lib\" -Force -ErrorAction SilentlyContinue
          Copy-Item "$src\lib\libwinpthread*" "$dst\lib\" -Force -ErrorAction SilentlyContinue
          Copy-Item "$src\lib\crt*" "$dst\lib\" -Force -ErrorAction SilentlyContinue

          Write-Host "Done. Size:"
          (Get-ChildItem $dst -Recurse | Measure-Object -Property Length -Sum).Sum / 1MB

      - name: Commit to repo
        shell: powershell
        run: |
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"
          git add libs/windows-x64/gcc/
          git diff --staged --quiet
          if ($LASTEXITCODE -ne 0) {
            git commit -m "ci: bundle portable MinGW-w64 gcc for Windows"
            git push
          } else {
            Write-Host "No changes to commit"
          }