Install llvm for arm

Author: Eclips4

.github/workflows/reusable-windows-msi.yml

@@ -30,12 +30,25 @@ jobs:
       with:
         targets: i686-pc-windows-msvc,x86_64-pc-windows-msvc,aarch64-pc-windows-msvc
     - name: Install LLVM for bindgen
+      if: inputs.arch != 'arm64'
       shell: cmd
       run: |
         choco install llvm --allow-downgrade --no-progress --version 21.1.0
         if not exist "C:\Program Files\LLVM\bin\libclang.dll" exit /b 1
         echo LIBCLANG_PATH=C:\Program Files\LLVM\bin>> "%GITHUB_ENV%"
         echo LLVMInstallDir=C:\Program Files\LLVM>> "%GITHUB_ENV%"
+    # Chocolatey's LLVM package only ships x64 binaries, which an ARM64-native
+    # cargo process cannot load.  Install the official ARM64 build directly.
+    - name: Install LLVM for bindgen (ARM64)
+      if: inputs.arch == 'arm64'
+      shell: pwsh
+      run: |
+        $installer = Join-Path $env:RUNNER_TEMP 'LLVM-21.1.0-woa64.exe'
+        Invoke-WebRequest 'https://github.com/llvm/llvm-project/releases/download/llvmorg-21.1.0/LLVM-21.1.0-woa64.exe' -OutFile $installer
+        Start-Process -Wait -FilePath $installer -ArgumentList '/S','/D=C:\Program Files\LLVM'
+        if (!(Test-Path 'C:\Program Files\LLVM\bin\libclang.dll')) { exit 1 }
+        echo "LIBCLANG_PATH=C:\Program Files\LLVM\bin" >> $env:GITHUB_ENV
+        echo "LLVMInstallDir=C:\Program Files\LLVM" >> $env:GITHUB_ENV
     - name: Build CPython installer
       run: ./Tools/msi/build.bat --doc -"${ARCH}"
       shell: bash

.github/workflows/reusable-windows.yml

@@ -33,12 +33,25 @@ jobs:
       with:
         targets: i686-pc-windows-msvc,x86_64-pc-windows-msvc,aarch64-pc-windows-msvc
     - name: Install LLVM for bindgen
+      if: inputs.arch != 'arm64'
       shell: cmd
       run: |
         choco install llvm --allow-downgrade --no-progress --version 21.1.0
         if not exist "C:\Program Files\LLVM\bin\libclang.dll" exit /b 1
         echo LIBCLANG_PATH=C:\Program Files\LLVM\bin>> "%GITHUB_ENV%"
         echo LLVMInstallDir=C:\Program Files\LLVM>> "%GITHUB_ENV%"
+    # Chocolatey's LLVM package only ships x64 binaries, which an ARM64-native
+    # cargo process cannot load.  Install the official ARM64 build directly.
+    - name: Install LLVM for bindgen (ARM64)
+      if: inputs.arch == 'arm64'
+      shell: pwsh
+      run: |
+        $installer = Join-Path $env:RUNNER_TEMP 'LLVM-21.1.0-woa64.exe'
+        Invoke-WebRequest 'https://github.com/llvm/llvm-project/releases/download/llvmorg-21.1.0/LLVM-21.1.0-woa64.exe' -OutFile $installer
+        Start-Process -Wait -FilePath $installer -ArgumentList '/S','/D=C:\Program Files\LLVM'
+        if (!(Test-Path 'C:\Program Files\LLVM\bin\libclang.dll')) { exit 1 }
+        echo "LIBCLANG_PATH=C:\Program Files\LLVM\bin" >> $env:GITHUB_ENV
+        echo "LLVMInstallDir=C:\Program Files\LLVM" >> $env:GITHUB_ENV
     - name: Register MSVC problem matcher
       if: inputs.arch != 'Win32'
       run: echo "::add-matcher::.github/problem-matchers/msvc.json"