Add clang-cl jobs to azure

Author: isuruf

.azure-pipelines/ci.yml

@@ -138,13 +138,27 @@ jobs:
       win32:
         arch: win32
         buildOpt:
+        installClang: no
         testRunTitle: '$(Build.SourceBranchName)-win32'
         testRunPlatform: win32
       win64:
         arch: amd64
         buildOpt: '-p x64'
+        installClang: no
         testRunTitle: '$(Build.SourceBranchName)-win64'
         testRunPlatform: win64
+      win32_clang_cl:
+        arch: win32
+        buildOpt: '"/p:CLToolExe=clang-cl.exe" "/p:CLToolPath=C:\Program Files (x86)\LLVM\bin"'
+        installClang: yes
+        testRunTitle: '$(Build.SourceBranchName)-clang_cl-win32'
+        testRunPlatform: win32
+      win64_clang_cl:
+        arch: amd64
+        buildOpt: '-p x64 "/p:CLToolExe=clang-cl.exe" "/p:CLToolPath=C:\Program Files\LLVM\bin"'
+        installClang: yes
+        testRunTitle: '$(Build.SourceBranchName)-clang_cl-win64'
+        testRunPlatform: win64
     maxParallel: 4
 
   steps:

.azure-pipelines/windows-steps.yml

@@ -12,6 +12,18 @@ steps:
     Write-Host '##vso[task.setvariable variable=EXTERNALS_DIR]$(Build.BinariesDirectory)\externals'
   displayName: Update build locations
 
+- powershell: |
+    (New-Object System.Net.WebClient).DownloadFile("https://github.com/llvm/llvm-project/releases/download/llvmorg-9.0.1/LLVM-9.0.1-win32.exe", "LLVM-win.exe")
+    Start-Process .\LLVM-win.exe -ArgumentList '/S' -Wait
+  displayName: Install clang on win32
+  condition: and(eq('yes', variables['installClang']), eq('win32', variables['arch']))
+
+- powershell: |
+    (New-Object System.Net.WebClient).DownloadFile("https://github.com/llvm/llvm-project/releases/download/llvmorg-9.0.1/LLVM-9.0.1-win64.exe", "LLVM-win.exe")
+    Start-Process .\LLVM-win.exe -ArgumentList '/S' -Wait
+  displayName: Install clang on win64
+  condition: and(eq('yes', variables['installClang']), eq('amd64', variables['arch']))
+
 - script: PCbuild\build.bat -e $(buildOpt)
   displayName: 'Build CPython'
   env: