diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 1c70678..375a68b 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -64,13 +64,52 @@ jobs:
             parameters.txt
           retention-days: 7
 
-  # Build a cross compiler for Linux, targeting Windows.
-  linux:
+  linux-stage1:
     if: (github.event_name != 'schedule') || (github.repository == 'mstorsjo/llvm-mingw')
     needs: [prepare]
     runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
+      - name: Build
+        env:
+          LLVM_VERSION: ${{needs.prepare.outputs.LLVM_VERSION}}
+          TAG: ${{needs.prepare.outputs.TAG}}
+          SOURCE_DATE_EPOCH: ${{needs.prepare.outputs.COMMIT_DATE_UNIX}}
+          BUILD_DATE: ${{needs.prepare.outputs.BUILD_DATE}}
+        run: |
+          # Skip dynamic library dependencies that might make it harder to
+          # run the binaries on other distros (and that have little use within
+          # llvm-mingw).
+          LLVM_CMAKEFLAGS="-DLLVM_ENABLE_LIBXML2=OFF -DLLDB_ENABLE_PYTHON=OFF" ./build-all.sh $(pwd)/install/llvm --stage1 --llvm-only
+          .github/workflows/store-version.sh install/llvm/versions.txt
+          cd install
+          DISTRO=ubuntu-$(grep DISTRIB_RELEASE /etc/lsb-release | cut -f 2 -d =)-$(uname -m)
+          NAME=llvm-$TAG-$DISTRO
+          mv llvm $NAME
+          tar -Jcf ../$NAME.tar.xz --format=ustar --numeric-owner --owner=0 --group=0 --sort=name --mtime="$BUILD_DATE" $NAME
+      - uses: actions/upload-artifact@v4
+        with:
+          name: linux-llvm-x86_64
+          path: |
+            llvm-*.tar.xz
+          retention-days: 7
+
+  # Build a cross compiler for Linux, targeting Windows.
+  linux:
+    if: (github.event_name != 'schedule') || (github.repository == 'mstorsjo/llvm-mingw')
+    needs: [prepare, linux-stage1]
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/download-artifact@v4
+        with:
+          name: linux-llvm-x86_64
+      - name: Unpack stage1 Clang
+        run: |
+          tar -Jxf llvm-*.tar.xz
+          rm llvm-*.tar.xz
+          sudo mv llvm* /opt/llvm
+          echo /opt/llvm/bin >> $GITHUB_PATH
       - name: Build
         env:
           LLVM_VERSION: ${{needs.prepare.outputs.LLVM_VERSION}}
@@ -82,7 +121,7 @@ jobs:
           # Skip dynamic library dependencies that might make it harder to
           # run the binaries on other distros (and that have little use within
           # llvm-mingw).
-          LLVM_CMAKEFLAGS="-DLLVM_ENABLE_LIBXML2=OFF -DLLDB_ENABLE_PYTHON=OFF" ./build-all.sh $(pwd)/install/llvm-mingw
+          LLVM_CMAKEFLAGS="-DLLVM_ENABLE_LIBXML2=OFF -DLLDB_ENABLE_PYTHON=OFF" ./build-all.sh $(pwd)/install/llvm-mingw --with-clang
           .github/workflows/store-version.sh install/llvm-mingw/versions.txt
           ./test-libcxx-module.sh $(pwd)/install/llvm-mingw
           ./run-tests.sh $(pwd)/install/llvm-mingw
@@ -102,10 +141,19 @@ jobs:
   # libraries that were built in the 'linux' step above.
   linux-cross-aarch64:
     if: (github.event_name != 'schedule') || (github.repository == 'mstorsjo/llvm-mingw')
-    needs: [linux, prepare]
+    needs: [linux, linux-stage1, prepare]
     runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
+      - uses: actions/download-artifact@v4
+        with:
+          name: linux-llvm-x86_64
+      - name: Unpack stage1 Clang
+        run: |
+          tar -Jxf llvm-*.tar.xz
+          rm llvm-*.tar.xz
+          sudo mv llvm* /opt/llvm
+          echo /opt/llvm/bin >> $GITHUB_PATH
       - name: Build
         env:
           LLVM_VERSION: ${{needs.prepare.outputs.LLVM_VERSION}}
@@ -113,7 +161,7 @@ jobs:
           SOURCE_DATE_EPOCH: ${{needs.prepare.outputs.COMMIT_DATE_UNIX}}
         run: |
           sudo apt-get update && sudo apt-get install g++-aarch64-linux-gnu
-          ./build-all.sh $(pwd)/install/llvm-mingw --no-runtimes --host=aarch64-linux-gnu
+          ./build-all.sh $(pwd)/install/llvm-mingw --no-runtimes --host=aarch64-linux-gnu --with-clang
           .github/workflows/store-version.sh install/llvm-mingw/versions.txt
       - uses: actions/download-artifact@v4
         with:
@@ -183,13 +231,51 @@ jobs:
             llvm-mingw-linux.tar.xz
           retention-days: 7
 
-  # Build a cross compiler for macOS, targeting Windows.
-  macos:
+  macos-stage1:
     if: (github.event_name != 'schedule') || (github.repository == 'mstorsjo/llvm-mingw')
     needs: [prepare]
     runs-on: macos-latest
     steps:
       - uses: actions/checkout@v4
+      - name: Build
+        env:
+          LLVM_VERSION: ${{needs.prepare.outputs.LLVM_VERSION}}
+          TAG: ${{needs.prepare.outputs.TAG}}
+          SOURCE_DATE_EPOCH: ${{needs.prepare.outputs.COMMIT_DATE_UNIX}}
+          BUILD_DATE: ${{needs.prepare.outputs.BUILD_DATE}}
+        run: |
+          # Disable zstd and python. Both are available on the runners, but
+          # installed with homebrew, and only available in the native (arm64)
+          # form.
+          LLVM_CMAKEFLAGS="-DLLVM_ENABLE_ZSTD=OFF -DLLDB_ENABLE_PYTHON=OFF" ./build-all.sh $(pwd)/install/llvm --stage1 --llvm-only
+          .github/workflows/store-version.sh install/llvm/versions.txt
+          cd install
+          NAME=llvm-$TAG-macos-$(uname -m)
+          mv llvm $NAME
+          gtar -Jcf ../$NAME.tar.xz --format=ustar --numeric-owner --owner=0 --group=0 --sort=name --mtime="$BUILD_DATE" $NAME
+      - uses: actions/upload-artifact@v4
+        with:
+          name: macos-llvm
+          path: |
+            llvm-*.tar.xz
+          retention-days: 7
+
+  # Build a cross compiler for macOS, targeting Windows.
+  macos:
+    if: (github.event_name != 'schedule') || (github.repository == 'mstorsjo/llvm-mingw')
+    needs: [prepare, macos-stage1]
+    runs-on: macos-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/download-artifact@v4
+        with:
+          name: macos-llvm
+      - name: Unpack stage1 Clang
+        run: |
+          tar -Jxf llvm-*.tar.xz
+          rm llvm-*.tar.xz
+          mv llvm* $HOME/llvm
+          echo $HOME/llvm/bin >> $GITHUB_PATH
       - name: Build
         env:
           LLVM_VERSION: ${{needs.prepare.outputs.LLVM_VERSION}}
@@ -203,7 +289,8 @@ jobs:
           # form. Therefore, autodetection will pick them up, but linking
           # universal binaries fails as those libraries are unavailable in the
           # other (x86_64) architecture form.
-          MACOS_REDIST=1 LLVM_CMAKEFLAGS="-DLLVM_ENABLE_ZSTD=OFF -DLLDB_ENABLE_PYTHON=OFF" ./build-all.sh $(pwd)/install/llvm-mingw
+          export SDKROOT=$(xcrun --show-sdk-path)
+          MACOS_REDIST=1 LLVM_CMAKEFLAGS="-DLLVM_ENABLE_ZSTD=OFF -DLLDB_ENABLE_PYTHON=OFF" ./build-all.sh $(pwd)/install/llvm-mingw --with-clang
           .github/workflows/store-version.sh install/llvm-mingw/versions.txt
           ./test-libcxx-module.sh $(pwd)/install/llvm-mingw
           ./run-tests.sh $(pwd)/install/llvm-mingw
@@ -689,6 +776,8 @@ jobs:
         run: |
           rm -rf linux-asserts*
           rm -rf msys2*
+          rm -rf linux-llvm-*
+          rm -rf macos-llvm*
           mv *-toolchain/*.zip *-toolchain/*.tar.xz .
       - name: Upload binaries
         env: