Repository navigation
2026.9.28.2: one resolver for the runtime beside a Windows program, header tracking on every host, one statement per fact, conditional tables by specificity #1
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| name: measure windows tool crt | |
| # The measurement of the 2026-09-28 ecosystem design, §2.9 (task M2), which | |
| # gates the removal of the MSVC C++ runtime from xim:qt-base (task I2). | |
| # | |
| # Qt's host tools (moc.exe; lrelease.exe, which loads Qt6Core.dll) are built | |
| # with MSVC and need its C++ runtime to start. Once the payload carries no copy, | |
| # the only copy they can reach is the one the engine puts first on the PATH of | |
| # every action of a build for a Windows target: the toolset's. The system | |
| # directory precedes PATH in the loader's search order, and every GitHub | |
| # Windows image has the VC++ redistributable there, so the system's copy is | |
| # hidden while the legs run; without that the first leg could not fail. | |
| # | |
| # Two rows. On `visual-studio` the toolset's runtime is the Visual Studio | |
| # redistributable. On `bare` Visual Studio is masked and the project names the | |
| # managed toolset `msvc@14.44.35207`, whose payload carries its own. | |
| # | |
| # M-a each tool, started from the CRT-free payload with no runtime | |
| # reachable, fails to start: the measurement can fail. | |
| # M-b each tool, started by the candidate's recorded action edge, starts. | |
| # M-c (a reading) the same edge recorded by the released mcpp; expected to | |
| # fail, as the state before the change. | |
| # | |
| # The legs run the recorded edge with ninja directly, after the build that | |
| # recorded it, so that nothing else (the xlings the engine resolves through, | |
| # for instance) has to start while the system's runtime is hidden. | |
| on: | |
| pull_request: | |
| branches: [ main ] | |
| paths: | |
| - '.github/workflows/measure-windows-tool-crt.yml' | |
| - 'src/build/ninja_backend.cppm' | |
| - 'src/build/runtime_placement.cppm' | |
| - 'src/cli.cppm' | |
| workflow_dispatch: | |
| concurrency: | |
| group: measure-${{ github.workflow }}-${{ github.ref }} | |
| cancel-in-progress: true | |
| jobs: | |
| candidate: | |
| name: candidate mcpp (windows x64) | |
| runs-on: windows-latest | |
| timeout-minutes: 45 | |
| steps: | |
| - uses: actions/checkout@v4 | |
| - uses: ./.github/actions/bootstrap-mcpp | |
| - name: Build the candidate from this commit | |
| shell: bash | |
| run: | | |
| export MCPP_VENDORED_XLINGS="$XLINGS_BIN" | |
| "$MCPP" build | |
| exe=$(find target -name mcpp.exe -path '*/bin/*' -printf '%T@ %p\n' | sort -rn | head -1 | cut -d' ' -f2-) | |
| test -n "$exe" || { echo "::error::no mcpp.exe under target/"; exit 1; } | |
| mkdir -p candidate | |
| # The program and what the build placed beside it (its own C++ | |
| # runtime among them), so it starts while the system's copy is hidden. | |
| cp "$(dirname "$exe")"/*.exe "$(dirname "$exe")"/*.dll candidate/ 2>/dev/null || cp "$exe" candidate/ | |
| ls candidate | |
| candidate/mcpp.exe --version | |
| - uses: actions/upload-artifact@v4 | |
| with: | |
| name: measure-candidate | |
| path: candidate | |
| measure: | |
| name: measure (${{ matrix.row }}) | |
| needs: candidate | |
| runs-on: windows-latest | |
| timeout-minutes: 60 | |
| strategy: | |
| fail-fast: false | |
| matrix: | |
| row: [visual-studio, bare] | |
| env: | |
| XLINGS_NON_INTERACTIVE: '1' | |
| steps: | |
| - uses: actions/checkout@v4 | |
| - uses: actions/download-artifact@v4 | |
| with: | |
| name: measure-candidate | |
| path: candidate | |
| # The same mask as ci-windows.yml's bare-Windows row, applied before | |
| # anything touches Visual Studio. | |
| - name: Mask Visual Studio | |
| if: matrix.row == 'bare' | |
| shell: pwsh | |
| run: | | |
| $ErrorActionPreference = 'Continue' | |
| $vswhere = "C:\Program Files (x86)\Microsoft Visual Studio\Installer\vswhere.exe" | |
| if (Test-Path $vswhere) { Rename-Item $vswhere "vswhere.exe.masked" } | |
| Resolve-Path "C:\Program Files*\Microsoft Visual Studio\*\*\VC" -ErrorAction SilentlyContinue | ForEach-Object { | |
| try { Rename-Item -LiteralPath $_.Path -NewName "VC.masked" -ErrorAction Stop } | |
| catch { Write-Host " rename failed: $($_.Exception.Message)" } | |
| } | |
| foreach ($v in @('VSINSTALLDIR','VCINSTALLDIR','VCToolsInstallDir','VS170COMNTOOLS','VS160COMNTOOLS','VS150COMNTOOLS')) { | |
| "$v=" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8 | |
| } | |
| $left = Get-ChildItem "C:\Program Files*\Microsoft Visual Studio\*\*\VC\Tools\MSVC" -Directory -ErrorAction SilentlyContinue | |
| if ($left) { Write-Host "FAIL: VC tools still present after masking"; exit 1 } | |
| - uses: ./.github/actions/bootstrap-mcpp | |
| with: | |
| cache-target: 'false' | |
| - name: Install xim:qt-base 6.11.1 and remove its copy of the runtime | |
| shell: bash | |
| run: | | |
| "$XLINGS_BIN" install qt-base@6.11.1 -y | |
| QT="$(cygpath -u "$USERPROFILE")/.xlings/data/xpkgs/xim-x-qt-base/6.11.1" | |
| test -x "$QT/bin/moc.exe" || { echo "::error::no moc.exe in $QT/bin"; exit 1; } | |
| # What revision 1 of the recipe removes (task I2). | |
| ( cd "$QT/bin" && ls vcruntime140*.dll msvcp140*.dll concrt140.dll vccorlib140.dll 2>/dev/null; \ | |
| rm -f vcruntime140*.dll msvcp140*.dll concrt140.dll vccorlib140.dll ) | |
| echo "QT=$QT" >> "$GITHUB_ENV" | |
| - name: Record the tool edges with the candidate and with the released mcpp | |
| shell: bash | |
| run: | | |
| CAND="$PWD/candidate/mcpp.exe" | |
| QTW=$(cygpath -m "$QT") | |
| toolchain="" | |
| [ "${{ matrix.row }}" = bare ] && toolchain='[toolchain] | |
| windows = "msvc@14.44.35207"' | |
| for who in candidate released; do | |
| d="$RUNNER_TEMP/probe-$who" | |
| mkdir -p "$d/src" | |
| printf 'int main() { return 0; }\n' > "$d/src/main.cpp" | |
| printf 'class Probe : public QObject {\n Q_OBJECT\n};\n' > "$d/probe.h" | |
| printf '[package]\nname = "probe"\nversion = "0.1.0"\n\n%s\n' "$toolchain" > "$d/mcpp.toml" | |
| cat > "$d/build.mcpp" <<EOF | |
| import std; | |
| import mcpp; | |
| int main() { | |
| const std::string root = mcpp::manifest_dir(); | |
| const std::string out = mcpp::out_dir(); | |
| mcpp::action moc; | |
| moc.id = "tool-moc"; | |
| moc.role = mcpp::roles::check; | |
| moc.arg("$QTW/bin/moc.exe").arg((root + "/probe.h").c_str()) | |
| .arg("-o").arg((out + "/moc-probe.txt").c_str()) | |
| .input((root + "/probe.h").c_str()) | |
| .output((out + "/moc-probe.txt").c_str()) | |
| .submit(); | |
| mcpp::action lr; | |
| lr.id = "tool-lrelease"; | |
| lr.role = mcpp::roles::check; | |
| lr.arg("$QTW/bin/lrelease.exe").arg("-version") | |
| .output((out + "/lrelease-probe.stamp").c_str()) | |
| .submit(); | |
| return 0; | |
| } | |
| EOF | |
| m="$CAND"; [ "$who" = released ] && m="$MCPP" | |
| ( cd "$d" && "$m" build ) || { echo "::error::the $who build of the probe failed with the system's runtime present"; exit 1; } | |
| grep -rl "moc.exe" "$d/target" --include=build.ninja | head -1 > "$d/ninja-file" | |
| test -s "$d/ninja-file" || { echo "::error::no build.ninja records the moc edge ($who)"; exit 1; } | |
| echo "--- $who: the moc edge" | |
| grep -m1 "moc.exe" "$(cat "$d/ninja-file")" | |
| done | |
| NINJA=$(ls "$(cygpath -u "$USERPROFILE")"/.mcpp/registry/data/xpkgs/xim-x-ninja/*/ninja.exe 2>/dev/null | head -1) | |
| test -x "$NINJA" || NINJA=$(command -v ninja || true) | |
| test -x "$NINJA" || { echo "::error::no ninja.exe"; exit 1; } | |
| echo "NINJA=$NINJA" >> "$GITHUB_ENV" | |
| - name: Hide the system's C++ runtime | |
| shell: pwsh | |
| run: | | |
| $names = 'vcruntime140.dll','vcruntime140_1.dll','vcruntime140_threads.dll', | |
| 'msvcp140.dll','msvcp140_1.dll','msvcp140_2.dll','msvcp140_atomic_wait.dll', | |
| 'msvcp140_codecvt_ids.dll','concrt140.dll','vccorlib140.dll' | |
| foreach ($n in $names) { | |
| $p = Join-Path $env:SystemRoot "System32\$n" | |
| if (Test-Path $p) { | |
| takeown /f $p | Out-Null | |
| icacls $p /grant "Administrators:F" | Out-Null | |
| Rename-Item -LiteralPath $p -NewName "$n.measure-hidden" | |
| if (Test-Path $p) { Write-Host "FAIL: $p is still present"; exit 1 } | |
| Write-Host "hidden: $p" | |
| } | |
| } | |
| - name: "M-a: a tool with no runtime reachable does not start" | |
| shell: bash | |
| run: | | |
| for tool in moc lrelease; do | |
| if out=$(cd /c && PATH="/c/Windows/System32:/c/Windows" "$QT/bin/$tool.exe" -v 2>&1); then | |
| echo "::error::$tool.exe started with no C++ runtime reachable; this measurement cannot fail: $out" | |
| exit 1 | |
| fi | |
| echo "ok: M-a $tool.exe does not start without a runtime" | |
| done | |
| - name: "M-b: the candidate's action edge starts each tool" | |
| shell: bash | |
| run: | | |
| nf=$(cat "$RUNNER_TEMP/probe-candidate/ninja-file") | |
| bd=$(dirname "$nf") | |
| find "$bd" \( -name moc-probe.txt -o -name lrelease-probe.stamp \) -delete | |
| "$NINJA" -C "$bd" -t targets all | grep -E 'moc-probe.txt|lrelease-probe.stamp' | cut -d: -f1 > "$RUNNER_TEMP/edges" | |
| test -s "$RUNNER_TEMP/edges" || { echo "::error::no tool edge in the graph"; exit 1; } | |
| PATH="/usr/bin:/c/Windows/System32:/c/Windows" "$NINJA" -C "$bd" $(cat "$RUNNER_TEMP/edges") | |
| grep -q "Probe" "$(find "$bd" -name moc-probe.txt | head -1)" \ | |
| || { echo "::error::moc.exe ran but wrote no code for Probe"; exit 1; } | |
| echo "ok: M-b moc.exe and lrelease.exe start from the action's PATH (${{ matrix.row }})" | |
| - name: "M-c (reading): the released mcpp's action edge" | |
| shell: bash | |
| run: | | |
| nf=$(cat "$RUNNER_TEMP/probe-released/ninja-file") | |
| bd=$(dirname "$nf") | |
| find "$bd" \( -name moc-probe.txt -o -name lrelease-probe.stamp \) -delete | |
| edges=$("$NINJA" -C "$bd" -t targets all | grep -E 'moc-probe.txt|lrelease-probe.stamp' | cut -d: -f1) | |
| if PATH="/usr/bin:/c/Windows/System32:/c/Windows" "$NINJA" -C "$bd" $edges > "$RUNNER_TEMP/released.log" 2>&1; then | |
| echo "READING M-c: the released mcpp's edge started the tools (${{ matrix.row }})" | |
| else | |
| echo "READING M-c: the released mcpp's edge did not start the tools (${{ matrix.row }}):" | |
| tail -5 "$RUNNER_TEMP/released.log" | |
| fi | |
| # In bash: Git Bash does not use the MSVC runtime, and pwsh may. | |
| - name: Restore the system's C++ runtime | |
| if: always() | |
| shell: bash | |
| run: | | |
| for f in /c/Windows/System32/*.measure-hidden; do | |
| [ -e "$f" ] && mv "$f" "${f%.measure-hidden}" && echo "restored: ${f%.measure-hidden}" | |
| done | |
| true |