[llvm] [Workflows] Re-write release-binaries workflow (PR #89521)

[Tobias Hieta via llvm-commits]

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@@ -109,81 +100,216 @@ jobs:
       uses: hendrikmuhs/ccache-action at ca3acd2731eef11f1572ccb126356c2f9298d35e # v1.2.9
       with:
         max-size: 250M
-        key: sccache-${{ matrix.os }}-release
+        key: sccache-${{ runner.os }}-release
         variant: sccache
 
-    - name: Build Clang
+    - name: Build Stage 1 Clang
       run: |
-        cmake -G Ninja -C clang/cmake/caches/Release.cmake -DCMAKE_C_COMPILER_LAUNCHER=sccache -DCMAKE_CXX_COMPILER_LAUNCHER=sccache -DCMAKE_POSITION_INDEPENDENT_CODE=ON -S llvm -B build
-        ninja -v -C build clang
+        sudo chown $USER:$USER /mnt/
+        mkdir -p /mnt/build
+        cmake -G Ninja -C clang/cmake/caches/Release.cmake -DCMAKE_C_COMPILER_LAUNCHER=sccache -DCMAKE_CXX_COMPILER_LAUNCHER=sccache -DCMAKE_POSITION_INDEPENDENT_CODE=ON -S llvm -B /mnt/build
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tru wrote:

do we need to pass the position independent option here? I thought on was the default?

https://github.com/llvm/llvm-project/pull/89521