DO NOT MERGE: run windows builder in PR

Author: RalfJung

.github/workflows/ci.yml

@@ -62,6 +62,13 @@ jobs:
           - name: x86_64-gnu-tools
             os: ubuntu-20.04-16core-64gb
             env: {}
+          - name: x86_64-msvc-ext
+            env:
+              SCRIPT: python x.py --stage 2 test src/tools/cargotest src/tools/cargo && src/ci/docker/host-x86_64/x86_64-gnu-tools/checktools.sh x.py /tmp/toolstate/toolstates.json windows
+              HOST_TARGET: x86_64-pc-windows-msvc
+              RUST_CONFIGURE_ARGS: "--build=x86_64-pc-windows-msvc --enable-lld --save-toolstates=/tmp/toolstate/toolstates.json"
+              DEPLOY_TOOLSTATES_JSON: toolstates-windows.json
+            os: windows-2019-8core-32gb
     timeout-minutes: 600
     runs-on: "${{ matrix.os }}"
     steps:

src/ci/github-actions/ci.yml

@@ -336,6 +336,14 @@ jobs:
           - name: x86_64-gnu-tools
             <<: *job-linux-16c
 
+          - name: x86_64-msvc-ext
+            env:
+              SCRIPT: python x.py --stage 2 test src/tools/cargotest src/tools/cargo && src/ci/docker/host-x86_64/x86_64-gnu-tools/checktools.sh x.py /tmp/toolstate/toolstates.json windows
+              HOST_TARGET: x86_64-pc-windows-msvc
+              RUST_CONFIGURE_ARGS: --build=x86_64-pc-windows-msvc --enable-lld --save-toolstates=/tmp/toolstate/toolstates.json
+              DEPLOY_TOOLSTATES_JSON: toolstates-windows.json
+            <<: *job-windows-8c
+
   auto:
     <<: *base-ci-job
     name: auto - ${{ matrix.name }}