WIP: Only run test-toolchain, with a prebuilt toolchain

Author: mstorsjo

.github/workflows/build.yml

@@ -19,7 +19,7 @@ jobs:
   # slightly more, when we know a separate build of the same version but with
   # assertions enabled, has passed some amount of tests.
   prepare:
-    if: (github.event_name != 'schedule') || (github.repository == 'mstorsjo/llvm-mingw')
+    if: false
     runs-on: ubuntu-latest
     outputs:
       LLVM_VERSION: ${{steps.get-versions.outputs.LLVM_VERSION}}
@@ -330,7 +330,6 @@ jobs:
   # Run llvm-mingw's tests with the cross-built toolchains from above.
   test-toolchain:
     if: (github.event_name != 'schedule') || (github.repository == 'mstorsjo/llvm-mingw')
-    needs: [linux-cross-windows]
     defaults:
       run:
         shell: msys2 {0}
@@ -350,11 +349,9 @@ jobs:
           install: >-
             unzip
             make
-      - uses: actions/download-artifact@v4
-        with:
-          name: windows-ucrt-${{matrix.arch}}-toolchain
       - name: Unpack toolchain
         run: |
+          curl -LO https://martin.st/temp/llvm-mingw-arm64ec-ucrt-${{matrix.arch}}.zip
           unzip -q llvm-mingw-*.zip
           rm llvm-mingw-*.zip
           mv llvm-mingw-* /llvm-mingw