Fix Windows build on GitHub CI

Commit 54ad644 removed a test because the required version of Windows SDK to build Dawn is 22621. However, GitHub Action Windows runner uses SDK version 20348 by default.

This PR uses [fbactions/setup-winsdk@v2](https://github.com/fbactions/setup-winsdk) to install the target version of Windows SDK, but this is not enough so we also add env variable to force SDK detection. Both env variables and cmake variable seem to be required, the former are used by DXC's `FindD3D12` script and others are for CMake's generic SDK detection.

Example of successful CI run: https://github.com/eliemichel/dawn-prebuilt/actions/runs/11861028908/job/33057504211

This is an imported pull request from
#23

GITHUB_PR_HEAD_SHA=dbaa1dcae87e7c5fd71d034c900eec979099388b
ORIGINAL_AUTHOR=Elie Michel <[email protected]>
GitOrigin-RevId: 1fbce97
Change-Id: I4b5a57c5063c3deff9f4a632ee553bc779dccbb4
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/215215
Reviewed-by: Corentin Wallez <[email protected]>
Commit-Queue: Corentin Wallez <[email protected]>
Reviewed-by: dan sinclair <[email protected]>

Author: eliemichel

.github/workflows/ci.yml

@@ -4,6 +4,7 @@ on:
   push:
     branches: [ "main" ]
   pull_request:
+  workflow_dispatch:
 
 concurrency:
   # Use github.run_id on main branch
@@ -12,6 +13,12 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.ref == 'refs/heads/main' && github.run_id || github.event.pull_request.number || github.ref }}
   cancel-in-progress: true
 
+env:
+  # Only relevant when building on Windows, to force DXC to use the version of
+  # the SDK that we install below with fbactions/setup-winsdk@v2
+  WIN10_SDK_PATH: "C:/Program Files (x86)/Windows Kits/10"
+  WIN10_SDK_VERSION: 10.0.22621.0
+
 jobs:
   cmake:
     strategy:
@@ -85,6 +92,17 @@ jobs:
     steps:
     - uses: actions/checkout@v4
 
+    - name: Extract Windows SDK build version
+      if: matrix.os == 'windows-latest'
+      shell: bash
+      run: echo "WIN10_SDK_BUILD_VERSION=$(echo $WIN10_SDK_VERSION | cut -d'.' -f3)" >> $GITHUB_ENV
+
+    - name: Set up Windows SDK
+      if: matrix.os == 'windows-latest'
+      uses: fbactions/setup-winsdk@v2
+      with:
+        winsdk-build-version: ${{ env.WIN10_SDK_BUILD_VERSION }}
+
     - name: Set up dependencies on linux
       if: matrix.container == 'dockcross/manylinux_2_28-x64:latest'
       run: >

.github/workflows/dawn-ci.cmake

@@ -1,6 +1,9 @@
 # This file caches variables which are platform specific.
 if (WIN32)
     set(DAWN_USE_BUILT_DXC ON CACHE BOOL "")
+    set(CMAKE_SYSTEM_VERSION "$ENV{WIN10_SDK_VERSION}" CACHE STRING "")
+    set(CMAKE_WINDOWS_KITS_10_DIR "$ENV{WIN10_SDK_PATH}" CACHE STRING "")
+    set(CMAKE_VS_WINDOWS_TARGET_PLATFORM_VERSION "$ENV{WIN10_SDK_VERSION}" CACHE STRING "")
 endif ()
 set(DAWN_FETCH_DEPENDENCIES ON CACHE BOOL "")
 set(DAWN_ENABLE_INSTALL ON CACHE BOOL "")