release.yml

name: release

# Self-host release: bootstrap mcpp from xlings (xim:mcpp), build the
# musl-static artefact via `mcpp pack --target x86_64-linux-musl -o ...`,
# inject xlings into the produced tarball for install.sh consumers,
# smoke-test, upload.

on:
  push:
    tags: [ 'v*' ]
  workflow_dispatch:
    inputs:
      tag:
        description: 'tag to (re)build — leave blank to derive `v<version>` from mcpp.toml and create the tag automatically'
        required: false

jobs:
  # A RELEASE IS GATED BY THE ECOSYSTEM'S OWN PROJECTS (the 2026-09-28 design,
  # WS10): they are built with the candidate first
  # (.github/release-canaries.toml), and the job that creates the tag needs
  # them. A downstream project validates the release in its own pull request.
  canaries:
    uses: ./.github/workflows/release-canaries.yml

  build-release:
    name: build + upload (linux / x86_64)
    needs: canaries
    runs-on: ubuntu-24.04
    permissions:
      contents: write   # required to create releases + push tags
    timeout-minutes: 60
    env:
      # mcpp resolves MCPP_HOME from the binary's location by default,
      # but here we want to share toolchains with the bootstrap sandbox,
      # so we pin to a known path.
      MCPP_HOME: /home/runner/.mcpp
    steps:
      # fetch-depth: 0 instead of fetch-tags: true — actions/checkout@v4
      # fails on push-tag triggers when both the ref'd tag and
      # `fetch-tags: true` are set:
      #   "Cannot fetch both <sha> and refs/tags/vX.Y.Z to refs/tags/vX.Y.Z"
      # Full-history fetch covers the resolve-tag step's needs without
      # that contention.
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Resolve target tag + commit
        id: resolve
        # Three trigger shapes converge here:
        #   1. push: refs/tags/vX.Y.Z   → use that tag, build at its commit
        #   2. workflow_dispatch with `tag` input set:
        #        - tag exists on remote → check it out (rebuild scenario)
        #        - tag doesn't exist    → use current HEAD; gh-release
        #          creates the tag at that commit on upload
        #   3. workflow_dispatch with no input → derive `v<version>` from
        #      mcpp.toml's [package].version, build at current HEAD;
        #      gh-release creates the tag.
        run: |
          if [ "${{ github.event_name }}" = "push" ]; then
            TAG="${{ github.ref_name }}"
          elif [ -n "${{ github.event.inputs.tag }}" ]; then
            TAG="${{ github.event.inputs.tag }}"
          else
            VER=$(awk -F '"' '/^version[[:space:]]*=/{print $2; exit}' mcpp.toml)
            test -n "$VER" || { echo 'failed to read [package].version from mcpp.toml'; exit 1; }
            TAG="v$VER"
          fi
          echo "tag=$TAG"           >> "$GITHUB_OUTPUT"
          echo "version=${TAG#v}"   >> "$GITHUB_OUTPUT"
          # If the tag exists on remote AND we're on workflow_dispatch,
          # check it out so we rebuild that exact commit. push-tag runs
          # already start at the tag commit.
          if [ "${{ github.event_name }}" = "workflow_dispatch" ] \
             && git rev-parse --verify "refs/tags/$TAG" >/dev/null 2>&1; then
            git checkout --detach "refs/tags/$TAG"
          fi
          echo "Resolved tag: $TAG (commit $(git rev-parse --short HEAD))"

      # Cache mcpp's sandbox: musl-gcc 15.1 + binutils + glibc + linux-headers
      # + patchelf + ninja is ~800 MB on disk; without this every release
      # rebuilds from cold install. Key on the workspace manifest so a
      # toolchain change in mcpp.toml refreshes the cache.
      - name: Cache mcpp sandbox
        uses: actions/cache@v4
        with:
          path: ~/.mcpp
          key: mcpp-sandbox-${{ runner.os }}-release-${{ hashFiles('mcpp.toml', '.xlings.json') }}
          restore-keys: |
            mcpp-sandbox-${{ runner.os }}-release-

      # Cache xlings + xim:mcpp install.
      - name: Cache xlings
        uses: actions/cache@v4
        with:
          path: ~/.xlings
          key: xlings-${{ runner.os }}-release-xl0462-${{ hashFiles('.xlings.json') }}
          restore-keys: |
            xlings-${{ runner.os }}-release-xl0462-

      - name: Bootstrap mcpp via xlings
        env:
          XLINGS_NON_INTERACTIVE: '1'
          # Pin xlings to a known-good version. The upstream install
          # script always grabs `latest` (no version override), so we
          # download + self-install manually to avoid broken releases.
          XLINGS_VERSION: '2026.10.26.1'
        run: |
          # BY VERSION, NOT BY PRESENCE. A restored ~/.xlings holds the
          # xlings of an earlier release, and this binary is the one the
          # tarball bundles: 2026.10.10.1 shipped xlings 2026.10.8.1 on
          # linux-x86_64 because one was present.
          have=$("$HOME/.xlings/subos/default/bin/xlings" --version 2>/dev/null | awk '{print $2}')
          if [ "$have" != "$XLINGS_VERSION" ]; then
            tarball="xlings-${XLINGS_VERSION}-linux-x86_64.tar.gz"
            bash "$GITHUB_WORKSPACE/.github/tools/fetch_release.sh" \
              "https://github.com/openxlings/xlings/releases/download/v${XLINGS_VERSION}/${tarball}" \
              "/tmp/${tarball}"
            tar -xzf "/tmp/${tarball}" -C /tmp
            "/tmp/xlings-${XLINGS_VERSION}-linux-x86_64/subos/default/bin/xlings" self install
          fi
          export PATH="$HOME/.xlings/subos/default/bin:$PATH"
          xlings --version
          test "$(xlings --version | awk '{print $2}')" = "$XLINGS_VERSION" || {
            echo "::error::the xlings this release bundles is $(xlings --version), not $XLINGS_VERSION"; exit 1; }
          # Pinned to .xlings.json — a bare `xlings install mcpp` resolves
          # "newest in this runner's index copy" and put 0.0.105 (below the
          # index floor) into this job. See .github/tools/install_pinned_mcpp.sh.
          MCPP=$(bash "$GITHUB_WORKSPACE/.github/tools/install_pinned_mcpp.sh" "$GITHUB_WORKSPACE")
          echo "MCPP=$MCPP" >> "$GITHUB_ENV"
          echo "XLINGS_BIN=$HOME/.xlings/subos/default/bin/xlings" >> "$GITHUB_ENV"

      - name: Build + pack release artefact (musl static)
        id: stage
        # Build for the musl-static target, strip the produced ELF, then
        # let `mcpp pack` assemble the tarball (binary + top-level wrapper
        # + README + LICENSE, contents at archive root). Inject xlings
        # afterwards so install.sh consumers get a single self-contained
        # bundle.
        run: |
          TAG="${{ steps.resolve.outputs.tag }}"
          VERSION="${{ steps.resolve.outputs.version }}"
          TARBALL_NAME="mcpp-${VERSION}-linux-x86_64.tar.gz"

          # Build first so we can strip the ELF before pack copies it.
          export MCPP_VENDORED_XLINGS="$XLINGS_BIN"
          "$MCPP" build --target x86_64-linux-musl
          ARTIFACT=$(find target/x86_64-linux-musl -type f -name mcpp | head -1)
          test -n "$ARTIFACT"
          file "$ARTIFACT" | grep -q 'statically linked'
          # NB: stripping here is pointless — `mcpp pack` below rebuilds the
          # binary and overwrites it, which is why every release up to and
          # including 2026.7.28.2 shipped an UNSTRIPPED bin/mcpp despite the
          # strip that used to live on this line. The payload is slimmed after
          # packing instead, in the inject step below.

          # Pack with the freshly-built mcpp (not the bootstrap) so any
          # fixes to the pack code path are exercised in the same release
          # they ship in. MCPP_HOME is forced so the new binary uses the
          # pinned sandbox instead of resolving relative to its own
          # location under target/.
          MCPP_HOME="$MCPP_HOME" "$ARTIFACT" pack \
              --target x86_64-linux-musl \
              --mode static \
              -o "${TARBALL_NAME}"

          # Inject xlings: extract → add registry/bin/xlings to the wrapper
          # dir → re-tar preserving the wrapper. Since 0.0.4 the bundled
          # xlings lives at <ROOT>/registry/bin/xlings (= <XLINGS_HOME>/bin/xlings).
          TARBALL="target/dist/${TARBALL_NAME}"
          WRAPPER="${TARBALL_NAME%.tar.gz}"
          test -f "$TARBALL"
          INJECT=$(mktemp -d)
          tar -xzf "$TARBALL" -C "$INJECT"
          mkdir -p "$INJECT/$WRAPPER/registry/bin"
          cp "$XLINGS_BIN" "$INJECT/$WRAPPER/registry/bin/xlings"
          chmod +x "$INJECT/$WRAPPER/registry/bin/xlings"
          # Slim AFTER pack (pack rebuilds bin/mcpp) and BEFORE tar. Asserts
          # the result, so a strip that silently stops working fails the
          # release instead of quietly shipping a 34.8MB tarball again.
          bash .github/tools/slim_linux_payload.sh "$INJECT/$WRAPPER"
          (cd "$INJECT" && tar -czf "$GITHUB_WORKSPACE/${TARBALL}" "$WRAPPER")
          rm -rf "$INJECT"

          # Stage final dist/ (tarball + sidecars) for upload.
          mkdir -p dist
          cp "$TARBALL" "dist/${TARBALL_NAME}"
          (cd dist && cp "${TARBALL_NAME}" "mcpp-linux-x86_64.tar.gz")
          (cd dist && sha256sum "${TARBALL_NAME}" "mcpp-linux-x86_64.tar.gz" > SHA256SUMS)
          (cd dist && sha256sum "${TARBALL_NAME}" > "${TARBALL_NAME}.sha256")
          (cd dist && sha256sum "mcpp-linux-x86_64.tar.gz" > "mcpp-linux-x86_64.tar.gz.sha256")

          # Top-level install.sh — fetched by `curl | bash`.
          cp install.sh dist/install.sh
          chmod +x dist/install.sh

          echo "tag=$TAG"           >> $GITHUB_OUTPUT
          echo "version=$VERSION"   >> $GITHUB_OUTPUT
          echo "tarball=${TARBALL_NAME}" >> $GITHUB_OUTPUT
          ls -la dist/

      - name: Smoke-test the bundled tarball
        # Extract to a scratch dir and run mcpp from there with MCPP_HOME
        # unset — proves the release artefact is genuinely self-contained.
        run: |
          VERSION="${{ steps.stage.outputs.version }}"
          TARBALL_NAME="${{ steps.stage.outputs.tarball }}"
          # Wrapper dir inside the tarball matches its stem (mcpp pack
          # ties the two together).
          WRAPPER="${TARBALL_NAME%.tar.gz}"
          SMOKE=$(mktemp -d)
          tar -xzf "dist/${TARBALL_NAME}" -C "$SMOKE"
          ROOT="$SMOKE/$WRAPPER"
          test -x "$ROOT/bin/mcpp"
          test -x "$ROOT/registry/bin/xlings"
          test -x "$ROOT/mcpp"
          file "$ROOT/bin/mcpp" | grep -q 'statically linked'
          env -u MCPP_HOME "$ROOT/bin/mcpp" --version
          env -u MCPP_HOME "$ROOT/bin/mcpp" --help | head -10
          # Top-level wrapper reports the same version we're shipping.
          env -u MCPP_HOME "$ROOT/mcpp" --version | grep -q "$VERSION"
          # MCPP_HOME should auto-resolve to the extracted root.
          out=$(env -u MCPP_HOME "$ROOT/bin/mcpp" self env)
          # R4 (mcpp#832): the binary pack rebuilt with this release's own
          # engine trims the paths it carries.
          bash .github/tools/check_release_paths.sh "$ROOT/bin/mcpp"
          echo "$out" | grep -q "MCPP_HOME *= *$ROOT"

      - name: Generate source tarball + xpkg.lua via mcpp publish
        # Use the freshly-built mcpp to produce the source tarball + xpkg
        # descriptor for mcpp-index. The release tarball wraps its
        # contents in a `<tarball-stem>/` directory so the extract path
        # is $PUB/$WRAPPER/bin/mcpp.
        run: |
          VERSION="${{ steps.stage.outputs.version }}"
          TARBALL_NAME="${{ steps.stage.outputs.tarball }}"
          WRAPPER="${TARBALL_NAME%.tar.gz}"
          PUB=$(mktemp -d)
          tar -xzf "dist/${TARBALL_NAME}" -C "$PUB"
          MCPP_BIN="$PUB/$WRAPPER/bin/mcpp"
          env -u MCPP_HOME "$MCPP_BIN" publish --dry-run --allow-dirty
          test -f "target/dist/mcpp-${VERSION}.tar.gz"
          test -f "target/dist/mcpp.lua"
          cp "target/dist/mcpp-${VERSION}.tar.gz" dist/
          cp "target/dist/mcpp.lua" dist/
          ls -la dist/

      - name: Extract release notes from CHANGELOG
        id: notes
        run: |
          TAG="${{ steps.stage.outputs.tag }}"
          VERSION="${{ steps.stage.outputs.version }}"
          awk -v v="$VERSION" '
            /^## \[/ {
              if (in_section) exit
              if ($0 ~ "\\[" v "\\]") { in_section=1; next }
            }
            in_section { print }
          ' CHANGELOG.md > dist/RELEASE_NOTES.md || true
          # A RELEASE IS OUTWARD-FACING AND PERMANENT: publishing one whose
          # notes silently came out empty is not a lesser failure than any
          # other defect this workflow guards against, and until now it
          # produced none — v2026.9.18.1 went out with its notes body reading
          # literally "(no CHANGELOG entry found for 2026.9.18.1)", because
          # CHANGELOG.md had no matching `## [<version>]` heading and this
          # step wrote a placeholder and moved on rather than stopping. Stop
          # instead: no matching section is an authoring mistake (the
          # section is missing, or its version string does not match what is
          # being tagged), and the fix belongs in CHANGELOG.md before the
          # release is retried, not in a release whose notes nobody reads.
          if [ ! -s dist/RELEASE_NOTES.md ]; then
            echo "::error::CHANGELOG.md has no '## [$VERSION]' section — refusing to publish a release with empty notes. Add that section (docs/92-release.md) and re-run, rather than let this placeholder ship: (no CHANGELOG entry found for $VERSION)"
            exit 1
          fi
          echo "--- RELEASE_NOTES.md ---"
          cat dist/RELEASE_NOTES.md

      - name: Create GitHub Release
        uses: softprops/action-gh-release@v2
        with:
          tag_name: ${{ steps.stage.outputs.tag }}
          name: ${{ steps.stage.outputs.tag }}
          body_path: dist/RELEASE_NOTES.md
          draft: false
          prerelease: false
          files: |
            dist/mcpp-${{ steps.stage.outputs.version }}-linux-x86_64.tar.gz
            dist/mcpp-${{ steps.stage.outputs.version }}-linux-x86_64.tar.gz.sha256
            dist/mcpp-linux-x86_64.tar.gz
            dist/mcpp-linux-x86_64.tar.gz.sha256
            dist/install.sh
            dist/SHA256SUMS
            dist/mcpp-${{ steps.stage.outputs.version }}.tar.gz
            dist/mcpp.lua

  build-linux-aarch64:
    name: build (linux / aarch64, cross)
    runs-on: ubuntu-24.04
    needs: build-release
    permissions:
      contents: write
    timeout-minutes: 70
    steps:
      - uses: actions/checkout@v4

      - name: Install system deps + qemu
        run: |
          # The runner image carries third-party apt lists (Google Chrome
          # among them) that this job does not use, and a transient
          # `Hash Sum mismatch` on one of them fails the whole update -- which
          # killed two cross-build jobs in setup, before a single byte was
          # compiled. Dropping the lists this job has no use for is what makes
          # the step's failure mean something about this job.
          #
          # BY CONTENT, NOT BY FILENAME. The first attempt removed
          # `google-chrome.list` and the update failed on the same URL: on
          # ubuntu-24.04 the runner writes deb822 `.sources` files, so the
          # name was a guess and the guess was wrong.
          sudo grep -rlE 'dl[.]google[.]com|packages[.]microsoft[.]com' \
               /etc/apt/sources.list.d/ 2>/dev/null | xargs -r sudo rm -f
          sudo apt-get update -qq
          sudo apt-get install -y curl git build-essential qemu-user-static
          qemu-aarch64-static --version | head -1

      - name: Resolve tag + version
        id: resolve
        run: |
          VERSION=$(grep -E '^version' mcpp.toml | head -1 | sed 's/.*"\([^"]*\)".*/\1/')
          echo "version=$VERSION" >> "$GITHUB_OUTPUT"
          echo "tag=v$VERSION"    >> "$GITHUB_OUTPUT"

      - name: Bootstrap mcpp via xlings
        env:
          XLINGS_NON_INTERACTIVE: '1'
          XLINGS_VERSION: '2026.10.26.1'
        run: |
          tarball="xlings-${XLINGS_VERSION}-linux-x86_64.tar.gz"
          bash "$GITHUB_WORKSPACE/.github/tools/fetch_release.sh" \
            "https://github.com/openxlings/xlings/releases/download/v${XLINGS_VERSION}/${tarball}" \
            "/tmp/${tarball}"
          tar -xzf "/tmp/${tarball}" -C /tmp
          "/tmp/xlings-${XLINGS_VERSION}-linux-x86_64/subos/default/bin/xlings" self install
          echo "$HOME/.xlings/subos/current/bin" >> "$GITHUB_PATH"
          echo "$HOME/.xlings/bin"               >> "$GITHUB_PATH"
          echo "XLINGS_BIN=$HOME/.xlings/subos/default/bin/xlings" >> "$GITHUB_ENV"

      - name: Bootstrap mcpp + refresh index (latest, GLOBAL)
        run: |
          xlings config --mirror GLOBAL 2>/dev/null || true
          xlings update -y 2>/dev/null || xlings update 2>/dev/null || true
          MCPP=$(bash "$GITHUB_WORKSPACE/.github/tools/install_pinned_mcpp.sh" "$GITHUB_WORKSPACE")
          echo "MCPP=$MCPP" >> "$GITHUB_ENV"
          "$MCPP" --version

      - name: Cross-build mcpp -> aarch64-linux-musl (this release's source)
        run: |
          export MCPP_VENDORED_XLINGS="$XLINGS_BIN"
          # "$MCPP", not a bare `mcpp`: the bare form runs the PATH shim, which
          # resolves to whatever version xvm has selected — so pinning the
          # bootstrap would have looked correct and changed nothing here.
          "$MCPP" self config --mirror GLOBAL 2>/dev/null || true
          # The published bootstrap mcpp predates aarch64 cross-build support
          # (the feature landed after the last release), so it resolves the
          # x86_64 host musl-gcc for an aarch64 target. Two-stage instead: build
          # THIS release's x86_64 mcpp first, then cross-build aarch64 with it.
          "$MCPP" build --target x86_64-linux-musl
          FRESH=$(find target/x86_64-linux-musl -type f -name mcpp | head -1)
          test -n "$FRESH"
          "$FRESH" build --target aarch64-linux-musl
          BIN=$(find target/aarch64-linux-musl -type f -name mcpp | head -1)
          test -n "$BIN"
          file "$BIN" | grep -q 'ARM aarch64'
          file "$BIN" | grep -q 'statically linked'
          echo "MCPP_AARCH64=$GITHUB_WORKSPACE/$BIN" >> "$GITHUB_ENV"

      - name: Package aarch64 release (+ bundle aarch64 xlings)
        id: stage
        run: |
          VERSION="${{ steps.resolve.outputs.version }}"
          TARBALL_NAME="mcpp-${VERSION}-linux-aarch64.tar.gz"
          WRAPPER="mcpp-${VERSION}-linux-aarch64"
          STAGING=$(mktemp -d)
          mkdir -p "$STAGING/$WRAPPER/bin"
          cp "$MCPP_AARCH64" "$STAGING/$WRAPPER/bin/mcpp"
          # The binary is aarch64, so the host x86_64 `strip` cannot touch it —
          # resolve a cross-capable one. Required, not best-effort: the old
          # `|| true` here meant a missing tool silently shipped a fat tarball.
          # (slim_linux_payload.sh runs after xlings is staged, below.)
          STRIP=$(find "$HOME/.mcpp" -name 'aarch64-linux-musl-strip' -type f 2>/dev/null | head -1)
          [ -n "$STRIP" ] || STRIP=$(command -v llvm-strip 2>/dev/null || true)
          [ -n "$STRIP" ] || STRIP=$(command -v aarch64-linux-gnu-strip 2>/dev/null || true)
          [ -n "$STRIP" ] || { echo "no aarch64-capable strip found"; exit 1; }
          echo "aarch64 strip: $STRIP"
          cp LICENSE "$STAGING/$WRAPPER/" 2>/dev/null || true
          cp README.md "$STAGING/$WRAPPER/" 2>/dev/null || true
          cat > "$STAGING/$WRAPPER/mcpp" << 'LAUNCHER'
          #!/bin/sh
          exec "$(dirname "$0")/bin/mcpp" "$@"
          LAUNCHER
          chmod +x "$STAGING/$WRAPPER/mcpp"
          # Bundle the aarch64 xlings so install.sh consumers on aarch64 get an
          # aarch64 xlings, not the x86_64 bootstrap one. The three literals
          # below are pinned to the same version as XLINGS_VERSION; they are
          # NOT interpolated from it, so check_version_pins.sh scans for them
          # explicitly (they were absent from the old lock-step comment).
          XLA="xlings-2026.10.26.1-linux-aarch64.tar.gz"
          # NOT fetch_release.sh: this asset is OPTIONAL and the `if` is the
          # point — an arch with no prebuilt xlings must fall through quietly,
          # while the helper retries a 404 five times before giving up. The one
          # flag that matters here is --retry-all-errors: `curl: (52) Empty
          # reply from server` is a transport error, so plain --retry does not
          # cover it.
          if curl -fsSL --retry 3 --retry-delay 2 --retry-all-errors \
               --connect-timeout 20 --max-time 600 -o "/tmp/$XLA" \
               "https://github.com/openxlings/xlings/releases/download/v2026.10.26.1/$XLA"; then
            tar -xzf "/tmp/$XLA" -C /tmp
            XLBIN=$(find /tmp/xlings-2026.10.26.1-linux-aarch64 -path '*/bin/xlings' -type f | head -1)
            if [ -n "$XLBIN" ]; then
              mkdir -p "$STAGING/$WRAPPER/registry/bin"
              cp "$XLBIN" "$STAGING/$WRAPPER/registry/bin/xlings"
              chmod +x "$STAGING/$WRAPPER/registry/bin/xlings"
            fi
          fi
          # Slim both shipped ELFs with the cross strip resolved above, and
          # assert the result (the vendored xlings was 86.9MB unstripped here).
          bash .github/tools/slim_linux_payload.sh "$STAGING/$WRAPPER" "$STRIP"
          mkdir -p dist
          (cd "$STAGING" && tar -czf "$GITHUB_WORKSPACE/dist/${TARBALL_NAME}" "$WRAPPER")
          cp "dist/${TARBALL_NAME}" "dist/mcpp-linux-aarch64.tar.gz"
          (cd dist && sha256sum "${TARBALL_NAME}"      > "${TARBALL_NAME}.sha256")
          (cd dist && sha256sum "mcpp-linux-aarch64.tar.gz" > "mcpp-linux-aarch64.tar.gz.sha256")
          echo "tarball=${TARBALL_NAME}" >> "$GITHUB_OUTPUT"
          ls -la dist/

      - name: Smoke-test the aarch64 tarball (qemu)
        run: |
          TARBALL_NAME="${{ steps.stage.outputs.tarball }}"
          WRAPPER="${TARBALL_NAME%.tar.gz}"
          SMOKE=$(mktemp -d)
          tar -xzf "dist/${TARBALL_NAME}" -C "$SMOKE"
          ver=$(qemu-aarch64-static "$SMOKE/$WRAPPER/bin/mcpp" --version)
          echo "$ver"; echo "$ver" | grep -q 'mcpp'

      - name: Upload aarch64 artifacts to release
        uses: softprops/action-gh-release@v2
        with:
          tag_name: ${{ steps.resolve.outputs.tag }}
          files: |
            dist/mcpp-${{ steps.resolve.outputs.version }}-linux-aarch64.tar.gz
            dist/mcpp-${{ steps.resolve.outputs.version }}-linux-aarch64.tar.gz.sha256
            dist/mcpp-linux-aarch64.tar.gz
            dist/mcpp-linux-aarch64.tar.gz.sha256

  build-macos:
    name: build (macOS / ARM64)
    runs-on: macos-15
    needs: build-release
    permissions:
      contents: write
    timeout-minutes: 30
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Resolve tag
        id: resolve
        run: |
          if [ "${{ github.event_name }}" = "push" ]; then
            TAG="${{ github.ref_name }}"
          elif [ -n "${{ github.event.inputs.tag }}" ]; then
            TAG="${{ github.event.inputs.tag }}"
          else
            VER=$(awk -F '"' '/^version[[:space:]]*=/{print $2; exit}' mcpp.toml)
            TAG="v$VER"
          fi
          echo "tag=$TAG"         >> "$GITHUB_OUTPUT"
          echo "version=${TAG#v}" >> "$GITHUB_OUTPUT"
          if [ "${{ github.event_name }}" = "workflow_dispatch" ] \
             && git rev-parse --verify "refs/tags/$TAG" >/dev/null 2>&1; then
            git checkout --detach "refs/tags/$TAG"
          fi

      - name: Cache xlings
        uses: actions/cache@v4
        with:
          path: ~/.xlings
          key: xlings-macos15-release-xl0462-${{ hashFiles('.xlings.json') }}
          restore-keys: |
            xlings-macos15-release-xl0462-

      - name: Bootstrap mcpp via xlings
        env:
          XLINGS_NON_INTERACTIVE: '1'
          XLINGS_VERSION: '2026.10.26.1'
        run: |
          # By version, not by presence (see the Linux job).
          have=$("$HOME/.xlings/subos/default/bin/xlings" --version 2>/dev/null | awk '{print $2}')
          if [ "$have" != "$XLINGS_VERSION" ]; then
            WORK=$(mktemp -d)
            tarball="xlings-${XLINGS_VERSION}-macosx-arm64.tar.gz"
            bash "$GITHUB_WORKSPACE/.github/tools/fetch_release.sh" \
              "https://github.com/openxlings/xlings/releases/download/v${XLINGS_VERSION}/${tarball}" \
              "${WORK}/${tarball}"
            tar -xzf "${WORK}/${tarball}" -C "${WORK}"
            "${WORK}/xlings-${XLINGS_VERSION}-macosx-arm64/subos/default/bin/xlings" self install
          fi
          export PATH="$HOME/.xlings/subos/default/bin:$PATH"
          xlings --version
          test "$(xlings --version | awk '{print $2}')" = "$XLINGS_VERSION" || {
            echo "::error::the xlings this release bundles is $(xlings --version), not $XLINGS_VERSION"; exit 1; }
          # Pinned to .xlings.json — a bare `xlings install mcpp` resolves
          # "newest in this runner's index copy" and put 0.0.105 (below the
          # index floor) into this job. See .github/tools/install_pinned_mcpp.sh.
          MCPP=$(bash "$GITHUB_WORKSPACE/.github/tools/install_pinned_mcpp.sh" "$GITHUB_WORKSPACE")
          echo "MCPP=$MCPP" >> "$GITHUB_ENV"
          echo "XLINGS_BIN=$HOME/.xlings/subos/default/bin/xlings" >> "$GITHUB_ENV"

      - name: Build mcpp from source (two-stage self-host)
        env:
          # macOS min-version support: target macOS 14 so the release runs
          # on 14.0+ instead of only the runner's OS (the official LLVM
          # static libc++ archives are built for macOS 14 — going lower
          # needs a custom libc++ build, tracked as follow-up). Needs
          # static LLVM libc++ — the system libc++ on older macOS lacks
          # LLVM-20-era C++23 symbols (std::print's __is_posix_terminal
          # etc.; minos-14 + dynamic libc++ dies at launch on macos-14 CI).
          # See xlings .agents/docs/2026-06-05-macos-min-version-support.md.
          MACOSX_DEPLOYMENT_TARGET: '14.0'
        run: |
          export PATH="$HOME/.xlings/subos/default/bin:$PATH"
          export MCPP_VENDORED_XLINGS="$XLINGS_BIN"

          # Stage 1: the bootstrap mcpp builds this release's source. The
          # bootstrap's macOS link path predates the staticStdlib
          # implementation (hardcoded -lc++), so stage 1 links the system
          # libc++ — fine, it only needs to RUN on this runner.
          "$MCPP" build
          STAGE1=$(find target -path "*/bin/mcpp" | head -1)
          STAGE1=$(cd "$(dirname "$STAGE1")" && pwd)/$(basename "$STAGE1")
          "$STAGE1" --version

          # Stage 2: this release's mcpp rebuilds itself — flags.cppm's
          # native staticStdlib link produces the static minos-14 binary.
          # NOTE: stage 2 lands in a NEW fingerprint directory (its
          # fingerprint includes the deployment target; the bootstrap's
          # did not) — pick the most recently modified binary, not the
          # first find hit.
          "$STAGE1" build --no-cache
          MCPP_BIN=$(ls -t $(find target -path "*/bin/mcpp" -type f) | head -1)
          MCPP_BIN=$(cd "$(dirname "$MCPP_BIN")" && pwd)/$(basename "$MCPP_BIN")
          test -x "$MCPP_BIN"
          file "$MCPP_BIN"
          otool -L "$MCPP_BIN"
          echo "=== LC_BUILD_VERSION (must be minos 14.0) ==="
          otool -l "$MCPP_BIN" | grep -A4 LC_BUILD_VERSION | head -6
          otool -l "$MCPP_BIN" | grep -A4 LC_BUILD_VERSION | grep -q "minos 14.0" \
            || { echo "FAIL: expected minos 14.0"; exit 1; }
          if otool -L "$MCPP_BIN" | grep -q "libc++"; then
            echo "FAIL: still linked against system libc++"; exit 1
          fi
          "$MCPP_BIN" --version
          echo "MCPP_BIN=$MCPP_BIN" >> "$GITHUB_ENV"

      - name: Package macOS release
        id: stage
        run: |
          VERSION="${{ steps.resolve.outputs.version }}"
          TARBALL_NAME="mcpp-${VERSION}-macosx-arm64.tar.gz"
          WRAPPER="mcpp-${VERSION}-macosx-arm64"

          # Create release layout
          STAGING=$(mktemp -d)
          mkdir -p "$STAGING/$WRAPPER/bin"
          cp "$MCPP_BIN" "$STAGING/$WRAPPER/bin/mcpp"
          # Strip (Mach-O)
          strip "$STAGING/$WRAPPER/bin/mcpp" 2>/dev/null || true
          # Copy metadata
          cp LICENSE "$STAGING/$WRAPPER/" 2>/dev/null || true
          cp README.md "$STAGING/$WRAPPER/" 2>/dev/null || true

          # Shell launcher (same as Linux)
          cat > "$STAGING/$WRAPPER/mcpp" << 'LAUNCHER'
          #!/bin/sh
          exec "$(dirname "$0")/bin/mcpp" "$@"
          LAUNCHER
          chmod +x "$STAGING/$WRAPPER/mcpp"

          # Bundle xlings for install.sh consumers
          XLINGS_BIN="$HOME/.xlings/subos/default/bin/xlings"
          if [ -x "$XLINGS_BIN" ]; then
            mkdir -p "$STAGING/$WRAPPER/registry/bin"
            cp "$XLINGS_BIN" "$STAGING/$WRAPPER/registry/bin/xlings"
            chmod +x "$STAGING/$WRAPPER/registry/bin/xlings"
          fi

          # Create tarball
          mkdir -p dist
          (cd "$STAGING" && tar -czf "$GITHUB_WORKSPACE/dist/${TARBALL_NAME}" "$WRAPPER")
          # Versionless alias
          cp "dist/${TARBALL_NAME}" "dist/mcpp-macosx-arm64.tar.gz"
          # SHA256
          (cd dist && shasum -a 256 "${TARBALL_NAME}" > "${TARBALL_NAME}.sha256")
          (cd dist && shasum -a 256 "mcpp-macosx-arm64.tar.gz" > "mcpp-macosx-arm64.tar.gz.sha256")

          echo "tarball=${TARBALL_NAME}" >> "$GITHUB_OUTPUT"
          ls -la dist/

      - name: Smoke-test the tarball
        run: |
          VERSION="${{ steps.resolve.outputs.version }}"
          TARBALL_NAME="${{ steps.stage.outputs.tarball }}"
          WRAPPER="${TARBALL_NAME%.tar.gz}"
          SMOKE=$(mktemp -d)
          tar -xzf "dist/${TARBALL_NAME}" -C "$SMOKE"
          "$SMOKE/$WRAPPER/bin/mcpp" --version
          "$SMOKE/$WRAPPER/mcpp" --version | grep -q "$VERSION"
          # R4 (mcpp#832): stage 2 is this release's own engine, and it trims
          # the paths the binary carries.
          bash .github/tools/check_release_paths.sh "$SMOKE/$WRAPPER/bin/mcpp"

      - name: Upload macOS artifacts to release
        uses: softprops/action-gh-release@v2
        with:
          tag_name: ${{ steps.resolve.outputs.tag }}
          files: |
            dist/mcpp-${{ steps.resolve.outputs.version }}-macosx-arm64.tar.gz
            dist/mcpp-${{ steps.resolve.outputs.version }}-macosx-arm64.tar.gz.sha256
            dist/mcpp-macosx-arm64.tar.gz
            dist/mcpp-macosx-arm64.tar.gz.sha256

  build-windows:
    name: build (Windows / x86_64)
    runs-on: windows-latest
    needs: build-release
    permissions:
      contents: write
    timeout-minutes: 45
    env:
      MCPP_HOME: C:\Users\runneradmin\.mcpp
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Resolve tag
        id: resolve
        shell: bash
        run: |
          if [ "${{ github.event_name }}" = "push" ]; then
            TAG="${{ github.ref_name }}"
          elif [ -n "${{ github.event.inputs.tag }}" ]; then
            TAG="${{ github.event.inputs.tag }}"
          else
            VER=$(awk -F '"' '/^version[[:space:]]*=/{print $2; exit}' mcpp.toml)
            TAG="v$VER"
          fi
          echo "tag=$TAG"         >> "$GITHUB_OUTPUT"
          echo "version=${TAG#v}" >> "$GITHUB_OUTPUT"
          if [ "${{ github.event_name }}" = "workflow_dispatch" ] \
             && git rev-parse --verify "refs/tags/$TAG" >/dev/null 2>&1; then
            git checkout --detach "refs/tags/$TAG"
          fi

      - name: Cache mcpp sandbox
        uses: actions/cache@v4
        with:
          path: ~\.mcpp
          key: mcpp-sandbox-${{ runner.os }}-release-${{ hashFiles('mcpp.toml', '.xlings.json') }}
          restore-keys: |
            mcpp-sandbox-${{ runner.os }}-release-

      - name: Cache xlings
        uses: actions/cache@v4
        with:
          path: ~\.xlings
          key: xlings-${{ runner.os }}-release-xl0462-${{ hashFiles('.xlings.json') }}
          restore-keys: |
            xlings-${{ runner.os }}-release-xl0462-

      - name: Bootstrap mcpp via xlings
        shell: bash
        env:
          XLINGS_NON_INTERACTIVE: '1'
          XLINGS_VERSION: '2026.10.26.1'
        run: |
          # Captured before the `cd` below, in POSIX form: this step never
          # returns to the workspace, and GITHUB_WORKSPACE is a backslash
          # Windows path that git-bash tools mangle.
          REPO_DIR="$(pwd)"
          WORK=$(mktemp -d)
          zipfile="xlings-${XLINGS_VERSION}-windows-x86_64.zip"
          bash "$GITHUB_WORKSPACE/.github/tools/fetch_release.sh" \
            "https://github.com/openxlings/xlings/releases/download/v${XLINGS_VERSION}/${zipfile}" \
            "${WORK}/${zipfile}"
          cd "${WORK}"
          unzip -q "${zipfile}"
          "$WORK/xlings-${XLINGS_VERSION}-windows-x86_64/subos/default/bin/xlings.exe" self install
          export PATH="$USERPROFILE/.xlings/subos/default/bin:$PATH"
          echo "$USERPROFILE/.xlings/subos/default/bin" >> "$GITHUB_PATH"
          xlings.exe --version
          test "$(xlings.exe --version | awk '{print $2}' | tr -d '\r')" = "$XLINGS_VERSION" || {
            echo "::error::the xlings this release bundles is not $XLINGS_VERSION"; exit 1; }
          # Pinned + version-scoped lookup. The old `find | head -1` returned
          # whichever version the directory walk reached first.
          MCPP=$(bash "$REPO_DIR/.github/tools/install_pinned_mcpp.sh" "$REPO_DIR")
          echo "MCPP=$MCPP" >> "$GITHUB_ENV"
          XLINGS_BIN=$(cygpath -w "$USERPROFILE/.xlings/subos/default/bin/xlings.exe")
          echo "XLINGS_BIN=$XLINGS_BIN" >> "$GITHUB_ENV"
          echo "XLINGS_BIN_UNIX=$USERPROFILE/.xlings/subos/default/bin/xlings.exe" >> "$GITHUB_ENV"
          echo "XLINGS_XPKGS=$USERPROFILE/.xlings/data/xpkgs" >> "$GITHUB_ENV"

      - name: Build mcpp from source (self-host)
        shell: bash
        run: |
          export MCPP_VENDORED_XLINGS="$XLINGS_BIN"

          "$MCPP" build
          # Pick the NEWEST mcpp.exe, not an arbitrary one: `target/` is
          # restored from cache and keeps a directory per build fingerprint,
          # so after a version bump the freshly built binary sits alongside
          # the previous release's. `find | head -1` returned whichever the
          # directory walk hit first — which is how a 0.0.106 build ran the
          # 0.0.105 binary and failed 01_help_and_version.
          MCPP_BIN=$(find target -name "mcpp.exe" -path "*/bin/*" -printf "%T@ %p\n" \
              | sort -rn | head -1 | cut -d" " -f2-)
          test -n "$MCPP_BIN" || { echo "FAIL: no mcpp.exe in target/"; exit 1; }
          MCPP_BIN=$(cd "$(dirname "$MCPP_BIN")" && pwd)/$(basename "$MCPP_BIN")
          echo "Self-hosted binary: $MCPP_BIN"
          "$MCPP_BIN" --version
          echo "MCPP_BIN=$MCPP_BIN" >> "$GITHUB_ENV"

      - name: Package Windows release zip
        id: stage
        shell: bash
        run: |
          VERSION="${{ steps.resolve.outputs.version }}"
          WRAPPER="mcpp-${VERSION}-windows-x86_64"
          ZIPNAME="${WRAPPER}.zip"

          STAGING=$(mktemp -d)
          mkdir -p "$STAGING/$WRAPPER/bin" "$STAGING/$WRAPPER/registry/bin"
          cp "$MCPP_BIN" "$STAGING/$WRAPPER/bin/mcpp.exe"

          # Windows batch launcher
          printf '@echo off\r\n"%%~dp0bin\\mcpp.exe" %%*\r\n' > "$STAGING/$WRAPPER/mcpp.bat"
          cp README.md "$STAGING/$WRAPPER/" 2>/dev/null || true
          cp LICENSE   "$STAGING/$WRAPPER/" 2>/dev/null || true

          # Bundle xlings.exe for install consumers
          if [ -f "$XLINGS_BIN_UNIX" ]; then
            cp "$XLINGS_BIN_UNIX" "$STAGING/$WRAPPER/registry/bin/xlings.exe"
          fi

          # Pack with 7z (available on windows-latest)
          mkdir -p dist
          (cd "$STAGING" && 7z a -tzip "$ZIPNAME" "$WRAPPER")
          cp "$STAGING/$ZIPNAME" "dist/$ZIPNAME"
          # Versionless alias
          cp "dist/$ZIPNAME" "dist/mcpp-windows-x86_64.zip"
          # SHA256
          (cd dist && sha256sum "$ZIPNAME" > "$ZIPNAME.sha256")
          (cd dist && sha256sum "mcpp-windows-x86_64.zip" > "mcpp-windows-x86_64.zip.sha256")

          echo "zipname=$ZIPNAME" >> "$GITHUB_OUTPUT"
          ls -la dist/

      - name: Smoke-test the packaged zip
        shell: bash
        run: |
          ZIPNAME="${{ steps.stage.outputs.zipname }}"
          WRAPPER="${ZIPNAME%.zip}"
          SMOKE=$(mktemp -d)
          (cd "$SMOKE" && unzip -q "$GITHUB_WORKSPACE/dist/$ZIPNAME")
          "$SMOKE/$WRAPPER/bin/mcpp.exe" --version
          "$SMOKE/$WRAPPER/bin/mcpp.exe" --help | head -5
          test -f "$SMOKE/$WRAPPER/registry/bin/xlings.exe"
          test -f "$SMOKE/$WRAPPER/mcpp.bat"
          echo "Smoke-test passed"

      - name: Upload Windows artifacts to release
        uses: softprops/action-gh-release@v2
        with:
          tag_name: ${{ steps.resolve.outputs.tag }}
          files: |
            dist/mcpp-${{ steps.resolve.outputs.version }}-windows-x86_64.zip
            dist/mcpp-${{ steps.resolve.outputs.version }}-windows-x86_64.zip.sha256
            dist/mcpp-windows-x86_64.zip
            dist/mcpp-windows-x86_64.zip.sha256

  # Seal the complete, non-draft release inventory only after every platform
  # uploader has finished.  The manifest is desired state for downstream
  # reconcilers: a rerun may reproduce it byte-for-byte, but may never replace
  # it with different bytes for the same tag.
  release-manifest:
    name: validate + seal release manifest
    needs: [build-release, build-linux-aarch64, build-macos, build-windows]
    runs-on: ubuntu-24.04
    permissions:
      contents: write
    timeout-minutes: 20
    env:
      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Resolve immutable release identity
        id: resolve
        run: |
          if [ "${{ github.event_name }}" = "push" ]; then
            TAG="${{ github.ref_name }}"
          elif [ -n "${{ github.event.inputs.tag }}" ]; then
            TAG="${{ github.event.inputs.tag }}"
          else
            VERSION=$(awk -F '"' '/^version[[:space:]]*=/{print $2; exit}' mcpp.toml)
            test -n "$VERSION" || { echo 'failed to read [package].version from mcpp.toml'; exit 1; }
            TAG="v$VERSION"
          fi
          git fetch --force origin "refs/tags/$TAG:refs/tags/$TAG"
          COMMIT=$(git rev-list -n 1 "refs/tags/$TAG")
          test -n "$COMMIT"
          echo "tag=$TAG"         >> "$GITHUB_OUTPUT"
          echo "version=${TAG#v}" >> "$GITHUB_OUTPUT"
          echo "commit=$COMMIT"   >> "$GITHUB_OUTPUT"

      - name: Generate, upload once, and refetch manifest
        run: |
          TAG="${{ steps.resolve.outputs.tag }}"
          VERSION="${{ steps.resolve.outputs.version }}"
          COMMIT="${{ steps.resolve.outputs.commit }}"
          AUDIT_ROOT=$(mktemp -d)
          mkdir -p "$AUDIT_ROOT/assets" "$AUDIT_ROOT/publish"

          gh api "repos/${GITHUB_REPOSITORY}/releases/tags/$TAG" \
            > "$AUDIT_ROOT/release.json"
          gh release download "$TAG" --repo "$GITHUB_REPOSITORY" \
            --dir "$AUDIT_ROOT/assets"
          # SHA256SUMS names every archive of the release, the four builds
          # and the source: the Linux job wrote it before the others had
          # uploaded theirs, so it named Linux x86_64 alone.
          (cd "$AUDIT_ROOT/assets" && ls mcpp-*.tar.gz mcpp-*.zip 2>/dev/null | LC_ALL=C sort \
             | xargs sha256sum > "$AUDIT_ROOT/SHA256SUMS")
          cat "$AUDIT_ROOT/SHA256SUMS"
          if ! cmp -s "$AUDIT_ROOT/SHA256SUMS" "$AUDIT_ROOT/assets/SHA256SUMS"; then
            gh release upload "$TAG" "$AUDIT_ROOT/SHA256SUMS" --clobber --repo "$GITHUB_REPOSITORY"
          fi
          python3 tools/release/generate_manifest.py \
            --release-json "$AUDIT_ROOT/release.json" \
            --assets-dir "$AUDIT_ROOT/assets" \
            --version "$VERSION" \
            --tag "$TAG" \
            --commit "$COMMIT" \
            --output "$AUDIT_ROOT/publish/mcpp-release.json"

          if [ -f "$AUDIT_ROOT/assets/mcpp-release.json" ]; then
            cmp "$AUDIT_ROOT/assets/mcpp-release.json" \
                "$AUDIT_ROOT/publish/mcpp-release.json"
            echo "Existing manifest is byte-identical; leaving it untouched."
          else
            gh release upload "$TAG" \
              "$AUDIT_ROOT/publish/mcpp-release.json" \
              --repo "$GITHUB_REPOSITORY"
          fi

          # Do not trust the upload command alone. Fetch the final public
          # inventory into a clean directory, recompute every payload digest,
          # regenerate desired state, and compare the published bytes.
          MANIFEST_VISIBLE=false
          for attempt in {1..12}; do
            if gh api "repos/${GITHUB_REPOSITORY}/releases/tags/$TAG" \
                 --jq '.assets[].name' | grep -Fxq mcpp-release.json; then
              MANIFEST_VISIBLE=true
              break
            fi
            echo "Waiting for mcpp-release.json API visibility ($attempt/12)"
            sleep 5
          done
          test "$MANIFEST_VISIBLE" = true
          mkdir -p "$AUDIT_ROOT/final-assets"
          gh api "repos/${GITHUB_REPOSITORY}/releases/tags/$TAG" \
            > "$AUDIT_ROOT/final-release.json"
          gh release download "$TAG" --repo "$GITHUB_REPOSITORY" \
            --dir "$AUDIT_ROOT/final-assets"
          test -f "$AUDIT_ROOT/final-assets/mcpp-release.json"
          python3 tools/release/generate_manifest.py \
            --release-json "$AUDIT_ROOT/final-release.json" \
            --assets-dir "$AUDIT_ROOT/final-assets" \
            --version "$VERSION" \
            --tag "$TAG" \
            --commit "$COMMIT" \
            --output "$AUDIT_ROOT/final-expected.json"
          cmp "$AUDIT_ROOT/final-assets/mcpp-release.json" \
              "$AUDIT_ROOT/final-expected.json"
          cat "$AUDIT_ROOT/final-assets/mcpp-release.json"
          echo "SEALED_RELEASE_MANIFEST=$AUDIT_ROOT/final-assets/mcpp-release.json" >> "$GITHUB_ENV"

      # Downstream notifications consume the identity sealed by THIS run,
      # including workflow_dispatch rebuilds of a tag other than main's version.
      - name: Save the sealed manifest for package notifications
        uses: actions/upload-artifact@v4
        with:
          name: mcpp-release-manifest
          path: ${{ env.SEALED_RELEASE_MANIFEST }}
          if-no-files-found: error
          overwrite: true # A rerun has already proved the public bytes identical.
          retention-days: 30

  # Publish this release into the xlings ecosystem, after ALL platform builds
  # have uploaded their assets and the immutable manifest gate has passed:
  #   ① mirror binaries → xlings-res/mcpp (GitHub + GitCode) so XLINGS_RES
  #      downloads resolve on every platform (incl. the CN/GitCode path);
  #   ② open a PR against openxlings/xim-pkgindex bumping mcpp to this version
  #      (a maintainer merges it — index git source is not on the critical path).
  # These publication steps are required for ecosystem completeness: their
  # failure leaves the GitHub Release object available but keeps this workflow
  # red, so post-release verification cannot report a complete release.
  # Shared vendored scripts live in .github/tools/ (kept in sync with xlings).
  publish-ecosystem:
    needs: release-manifest
    runs-on: ubuntu-latest
    # A4 hardening: a single stuck upload once held this job >1h (6h default
    # ceiling). The mirror script has per-file timeouts and (post-0.0.89)
    # batch-upload + ranged-GET verification — normal runs are minutes; 30
    # is the generous backstop (20 was hit by the old per-asset verify loop).
    timeout-minutes: 30
    env:
      XLINGS_RES_TOKEN: ${{ secrets.XLINGS_RES_TOKEN }}
      GITCODE_TOKEN: ${{ secrets.GITCODE_TOKEN }}
      XIM_PKGINDEX_TOKEN: ${{ secrets.XIM_PKGINDEX_TOKEN }}
    steps:
      - name: Checkout code
        uses: actions/checkout@v4
      - name: Determine version
        id: version
        run: echo "version=$(awk -F '\"' '/^version[[:space:]]*=/{print $2; exit}' mcpp.toml)" >> "$GITHUB_OUTPUT"

      - name: Mirror binaries to xlings-res/mcpp (gh + gtc)
        if: ${{ env.XLINGS_RES_TOKEN != '' }}
        # THIS MUST BE LONGER THAN THE SCRIPT'S OWN LEG DEADLINE, AND FOR
        # A LONG TIME IT WAS SHORTER.
        #
        # `mirror_res.sh` gives GitCode `MIRROR_LEG_DEADLINE_GTC=2400s` because
        # that host shapes inbound traffic; this step killed it at 600s, so the
        # script's budget could never be spent and the shorter of two
        # disagreeing limits always won. Every release since has ended the same
        # way — `The action … has timed out after 10 minutes`, GitHub's eight
        # assets uploaded in seconds and GitCode's three large ones cut off,
        # with only the small `.sha256` files through. v2026.8.25.1 and
        # v2026.8.25.2 both, measured.
        #
        # The paragraph this replaces described a design that no longer
        # exists: a per-asset `MIRROR_UPLOAD_TIMEOUT` of 180s. The script's own
        # comment records why it went ("the old per-asset cap failed four
        # releases in a row") — but this value, calibrated to it, stayed.
        #
        # 45 > 40 leaves the script room to reach its own deadline and report
        # what it abandoned by name, which is the visibility the value exists
        # for; the job's `timeout-minutes: 30` above is the outer backstop.
        timeout-minutes: 45
        env:
          GH_TOKEN: ${{ secrets.XLINGS_RES_TOKEN }}
        run: |
          chmod +x .github/tools/gtc .github/tools/mirror_res.sh
          export PATH="$PWD/.github/tools:$PATH"
          # A4: BLOCKING. Both mirror hosts serve users (GLOBAL + CN install
          # paths); an incomplete mirror must fail here, visibly, instead of
          # surfacing as a 404 in the first user's install (or fresh-install CI).
          bash .github/tools/mirror_res.sh mcpp "${{ steps.version.outputs.version }}"

      - name: Open index bump PR (xim-pkgindex)
        if: ${{ env.XIM_PKGINDEX_TOKEN != '' }}
        env:
          PKGINDEX_TOKEN: ${{ secrets.XIM_PKGINDEX_TOKEN }}
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          chmod +x .github/tools/bump_index.sh
          # A4: BLOCKING — a missing bump PR means the index never learns the
          # release exists and every post-release install of the new version 404s.
          # The index's own updater writes the PR (bump_index.sh says why);
          # it needs the GitCode mirror above to be complete.
          bash .github/tools/bump_index.sh mcpp "${{ steps.version.outputs.version }}"

      # Post-release verification (ci-fresh-install) is triggered via its
      # `workflow_run: [release]` hook — a platform-generated event that is
      # exempt from GITHUB_TOKEN trigger suppression and needs no cross-repo
      # PAT. (A PAT-based dispatch step lived here briefly; it never worked —
      # XIM_PKGINDEX_TOKEN's resource owner is the index org and cannot cover
      # this repository.)