ci: the released mcpp 2026.10.26.2

.github/workflows/ci.yml

@@ -7,11 +7,12 @@ name: CI
 #   platform   a platform module used outside `if constexpr' for its platform
 #              fails to LINK, and the same use in a discarded branch links (R5)
 #
-# The library is built with the mcpp under cross-validation: until mcpp
-# 2026.10.26.2 is released, a unit with a module map that imports another
-# package's module through a third (`mcpplibs.os.terminal' through
-# `mcpplibs.os.error') does not compile under GCC (mcpp part 2 design §10.2),
-# so the mcpp named by MCPP_SOURCE_REF is built and used.
+# The library is built with the released mcpp, 2026.10.26.2 or later: the
+# first that compiles a unit with a module map importing another package's
+# module through a third under GCC (`mcpplibs.os.terminal' through
+# `mcpplibs.os.error', mcpp part 2 design §10.2) and builds the ok images.
+# A dispatch may name a branch of mcpp instead (`mcpp_ref'), which is then
+# built and used.
 
 on:
   push:
@@ -25,7 +26,8 @@ on:
         default: ""
 
 env:
-  MCPP_SOURCE_REF: ${{ github.event.inputs.mcpp_ref || vars.MCPP_SOURCE_REF || 'release/2026.10.26.2' }}
+  MCPP_SOURCE_REF: ${{ github.event.inputs.mcpp_ref || vars.MCPP_SOURCE_REF || '' }}
+  MCPP_VERSION: 2026.10.26.2
   XLINGS_VERSION: v2026.10.26.1
   XLINGS_NON_INTERACTIVE: '1'
 
@@ -69,7 +71,7 @@ jobs:
         run: |
           for attempt in 1 2 3 4 5 6; do
             xlings update > /dev/null 2>&1 || true
-            if xlings install mcpp -y -g; then break; fi
+            if xlings install "mcpp@$MCPP_VERSION" -y -g; then break; fi
             [ "$attempt" = 6 ] && { echo "::error::mcpp could not be installed"; exit 1; }
             sleep 60
           done
@@ -140,15 +142,17 @@ jobs:
       - name: The mcpp that has the target
         run: |
           xlings update > /dev/null 2>&1 || true
-          xlings install mcpp -y -g
+          xlings install "mcpp@$MCPP_VERSION" -y -g
           mcpp self config --mirror GLOBAL
-          src="$RUNNER_TEMP/mcpp-src"
-          git clone --quiet --depth 1 --branch "$MCPP_SOURCE_REF" https://github.com/mcpp-community/mcpp.git "$src"
-          rm -f "$src/.xlings.json"
-          ( cd "$src" && mcpp build --release )
-          built=$(find "$src/target" -type f -name mcpp | head -1)
-          [ -n "$built" ] || { echo "::error::mcpp did not build"; exit 1; }
-          echo "$(cd "$(dirname "$built")" && pwd)" >> "$GITHUB_PATH"
+          if [ -n "${MCPP_SOURCE_REF:-}" ]; then
+            src="$RUNNER_TEMP/mcpp-src"
+            git clone --quiet --depth 1 --branch "$MCPP_SOURCE_REF" https://github.com/mcpp-community/mcpp.git "$src"
+            rm -f "$src/.xlings.json"
+            ( cd "$src" && mcpp build --release )
+            built=$(find "$src/target" -type f -name mcpp | head -1)
+            [ -n "$built" ] || { echo "::error::mcpp did not build"; exit 1; }
+            echo "$(cd "$(dirname "$built")" && pwd)" >> "$GITHUB_PATH"
+          fi
       - name: The suites, run here and built for the other architecture
         run: |
           set -euo pipefail
@@ -200,7 +204,7 @@ jobs:
           "$env:USERPROFILE\.xlings\subos\current\bin" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
       - name: okrun, built here
         run: |
-          xlings install mcpp -y -g
+          xlings install "mcpp@$MCPP_VERSION" -y -g
           mcpp self config --mirror GLOBAL
           mcpp toolchain install llvm 23.1.3
           mcpp toolchain default llvm@23.1.3