ndgrigorian · Nov 4, 2026 · Nov 4, 2026 · Nov 4, 2026 · Nov 4, 2026
@@ -1,8 +1,10 @@
-# Open source SYCL build deps, loaded by os-llvm-sycl-build.yml and bumped by
-# bump-sycl-deps.yml from intel/llvm devops/dependencies.json.
+# Open source SYCL build deps, loaded by os-llvm-sycl-build.yml and
+# os-llvm-sycl-build-windows.yml, and bumped by bump-sycl-deps.yml from
+# intel/llvm devops/dependencies.json.
 # Kept out of .github/workflows/ since GITHUB_TOKEN can't push workflow files.
 DRIVER_PATH=2026-WW28
 OCLCPUEXP_FN=oclcpuexp-2026.22.6.1.17_160000_rel.tar.gz
+WIN_OCLCPUEXP_FN=win-oclcpuexp-2026.22.6.1.17_160000_rel.zip
 TBB_URL=https://github.com/uxlfoundation/oneTBB/releases/download/v2023.1.0/
 TBB_INSTALL_DIR=oneapi-tbb-2023.1.0
 TBB_FN=oneapi-tbb-2023.1.0-lin.tgz
@@ -1,7 +1,8 @@
 name: Bump open source SYCL build deps
 
 # Syncs the oclcpuexp and oneTBB pins in .github/sycl-build-deps.env, used by
-# os-llvm-sycl-build.yml, with intel/llvm devops/dependencies.json.
+# os-llvm-sycl-build.yml and os-llvm-sycl-build-windows.yml, with intel/llvm
+# devops/dependencies.json.
 
 on:
   schedule:
@@ -63,16 +64,23 @@ jobs:
 
           OCL_TAG=$(jq -er '.linux.oclcpu.github_tag' "${DEPS}")
           OCL_URL=$(jq -er '.linux.oclcpu.url' "${DEPS}")
+          WIN_OCL_URL=$(jq -er '.windows.oclcpu.url' "${DEPS}")
           TBB_VER=$(jq -er '.linux.tbb.version' "${DEPS}")
           TBB_FULL_URL=$(jq -er '.linux.tbb.url' "${DEPS}")
           OCLCPUEXP_FN=${OCL_URL##*/}
+          WIN_OCLCPUEXP_FN=${WIN_OCL_URL##*/}
 
           # os-llvm-sycl-build.yml rebuilds these URLs from the pins
           [[ "${OCL_TAG}" =~ ^[0-9]{4}-WW[0-9]+$ ]] || fail "unexpected oclcpu tag: ${OCL_TAG}"
           [[ "${OCLCPUEXP_FN}" =~ ^oclcpuexp-[0-9A-Za-z._]+_rel\.tar\.gz$ ]] \
               || fail "unexpected oclcpu asset: ${OCLCPUEXP_FN}"
           [[ "${OCL_URL}" == "https://github.com/intel/llvm/releases/download/${OCL_TAG}/${OCLCPUEXP_FN}" ]] \
               || fail "unexpected oclcpu url: ${OCL_URL}"
+          # both platforms download from the same DRIVER_PATH release
+          [[ "${WIN_OCLCPUEXP_FN}" =~ ^win-oclcpuexp-[0-9A-Za-z._]+_rel\.zip$ ]] \
+              || fail "unexpected Windows oclcpu asset: ${WIN_OCLCPUEXP_FN}"
+          [[ "${WIN_OCL_URL}" == "https://github.com/intel/llvm/releases/download/${OCL_TAG}/${WIN_OCLCPUEXP_FN}" ]] \
+              || fail "unexpected Windows oclcpu url: ${WIN_OCL_URL}"
           [[ "${TBB_VER}" =~ ^[0-9]+\.[0-9]+\.[0-9]+$ ]] || fail "unexpected tbb version: ${TBB_VER}"
           [[ "${TBB_FULL_URL}" == "https://github.com/uxlfoundation/oneTBB/releases/download/v${TBB_VER}/oneapi-tbb-${TBB_VER}-lin.tgz" ]] \
               || fail "unexpected tbb url: ${TBB_FULL_URL}"
@@ -81,6 +89,7 @@ jobs:
             echo "llvm_sha=${LLVM_SHA}"
             echo "driver_tag=${OCL_TAG}"
             echo "oclcpuexp_fn=${OCLCPUEXP_FN}"
+            echo "win_oclcpuexp_fn=${WIN_OCLCPUEXP_FN}"
             echo "tbb_ver=${TBB_VER}"
             echo "tbb_url=${TBB_FULL_URL%/*}/"
             echo "tbb_fn=${TBB_FULL_URL##*/}"
@@ -91,6 +100,7 @@ jobs:
         env:
           DRIVER_TAG: ${{ steps.resolve.outputs.driver_tag }}
           OCLCPUEXP_FN: ${{ steps.resolve.outputs.oclcpuexp_fn }}
+          WIN_OCLCPUEXP_FN: ${{ steps.resolve.outputs.win_oclcpuexp_fn }}
           TBB_URL: ${{ steps.resolve.outputs.tbb_url }}
           TBB_FN: ${{ steps.resolve.outputs.tbb_fn }}
           TBB_DIR: ${{ steps.resolve.outputs.tbb_dir }}
@@ -99,6 +109,7 @@ jobs:
           sed -i -E \
             -e "s|^(DRIVER_PATH=).*|\1${DRIVER_TAG}|" \
             -e "s|^(OCLCPUEXP_FN=).*|\1${OCLCPUEXP_FN}|" \
+            -e "s|^(WIN_OCLCPUEXP_FN=).*|\1${WIN_OCLCPUEXP_FN}|" \
             -e "s|^(TBB_URL=).*|\1${TBB_URL}|" \
             -e "s|^(TBB_INSTALL_DIR=).*|\1${TBB_DIR}|" \
             -e "s|^(TBB_FN=).*|\1${TBB_FN}|" \
@@ -114,9 +125,10 @@ jobs:
           delete-branch: true
           labels: autoupdate
           commit-message: |
-            Bump oclcpuexp/oneTBB pins for os-llvm-sycl-build workflow
+            Bump oclcpuexp/oneTBB pins for os-llvm-sycl-build workflows
 
             oclcpuexp: ${{ steps.resolve.outputs.driver_tag }} / ${{ steps.resolve.outputs.oclcpuexp_fn }}
+            oclcpuexp (Windows): ${{ steps.resolve.outputs.win_oclcpuexp_fn }}
             oneTBB: ${{ steps.resolve.outputs.tbb_ver }}
             intel/llvm: ${{ steps.resolve.outputs.llvm_sha }}
           title: "Bump open source SYCL build dependencies"
@@ -128,7 +140,10 @@ jobs:
             | --- | --- |
             | intel/llvm driver release | `${{ steps.resolve.outputs.driver_tag }}` |
             | oclcpuexp | `${{ steps.resolve.outputs.oclcpuexp_fn }}` |
+            | oclcpuexp (Windows) | `${{ steps.resolve.outputs.win_oclcpuexp_fn }}` |
             | oneTBB | `${{ steps.resolve.outputs.tbb_ver }}` |
 
             Pull requests opened by this workflow don't trigger CI: run
-            **Build with Open Source LLVM SYCL compiler** on this branch before merging.
+            **Build with Open Source LLVM SYCL compiler** and
+            **Build with Open Source LLVM SYCL compiler on Windows** on this
+            branch before merging.
@@ -0,0 +1,180 @@
+name: Build with Open Source LLVM SYCL compiler on Windows
+on:
+  pull_request:
+  push:
+    branches: [master]
+  workflow_dispatch:
+    inputs:
+      nightly-tag:
+        description: "intel/llvm nightly tag, e.g. nightly-2026-11-03 (default: latest with a Windows build)"
+        required: false
+        default: ""
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+jobs:
+  install-compiler:
+    name: Build with nightly build of DPC++ toolchain on Windows
+    runs-on: windows-latest
+    timeout-minutes: 120
+
+    env:
+      GH_TOKEN: ${{ github.token }}
+      PINS: .github/sycl-build-deps.env
+
+    steps:
+      - name: Checkout repo
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+          fetch-depth: 0
+
+      - name: Load pinned SYCL build deps
+        shell: bash
+        run: |
+          set -euo pipefail
+          # checkout may convert line endings to CRLF
+          VARS=$(grep -E '^(DRIVER_PATH|WIN_OCLCPUEXP_FN)=' "${PINS}" | tr -d '\r' || true)
+          if [[ $(wc -l <<< "${VARS}") -ne 2 ]]; then
+              echo "::error::expected 2 pins in ${PINS}, got:"
+              echo "${VARS}"
+              exit 1
+          fi
+          echo "${VARS}" | tee -a "${GITHUB_ENV}"
+
+      - name: Resolve nightly build
+        shell: bash
+        env:
+          NIGHTLY_TAG: ${{ inputs.nightly-tag }}
+        run: |
+          set -euo pipefail
+          if [[ -z "${NIGHTLY_TAG}" ]]; then
+              NIGHTLY_TAG=$(gh api 'repos/intel/llvm/releases?per_page=30' \
+                  --jq '[.[] | select(.tag_name | startswith("nightly-"))
+                             | select(any(.assets[]; .name == "sycl_windows.tar.gz"))][0].tag_name // empty')
+          fi
+          if [[ ! "${NIGHTLY_TAG}" =~ ^nightly-[0-9]{4}-[0-9]{2}-[0-9]{2}$ ]]; then
+              echo "::error::unexpected nightly tag: ${NIGHTLY_TAG}"
+              exit 1
+          fi
+          echo "NIGHTLY_TAG=${NIGHTLY_TAG}" | tee -a "${GITHUB_ENV}"
+
+      - name: Download and install nightly and components
+        shell: pwsh
+        run: |
+          $ErrorActionPreference = 'Stop'
+          $PSNativeCommandUseErrorActionPreference = $true
+          $ProgressPreference = 'SilentlyContinue'
+
+          $root = Join-Path $env:RUNNER_TEMP 'sycl_bundle'
+          $compiler = Join-Path $root 'dpcpp_compiler'
+          $oclcpu = Join-Path $root 'oclcpuexp'
+          New-Item -ItemType Directory -Force -Path $compiler, $oclcpu | Out-Null
+
+          gh release download $env:NIGHTLY_TAG -R intel/llvm -p sycl_windows.tar.gz -D $root
+          $bundle = Join-Path $root 'sycl_windows.tar.gz'
+          & "$env:SystemRoot\System32\tar.exe" -xzf $bundle -C $compiler
+          Remove-Item $bundle
+
+          gh release download $env:DRIVER_PATH -R intel/llvm -p $env:WIN_OCLCPUEXP_FN -D $root
+          $zip = Join-Path $root $env:WIN_OCLCPUEXP_FN
+          Expand-Archive -Path $zip -DestinationPath $oclcpu
+          Remove-Item $zip
+
+          # register the CPU runtime with the ICD loader without install.bat;
+          # runner steps are elevated, so the loader ignores OCL_ICD_FILENAMES
+          $vendors = 'HKLM:\SOFTWARE\Khronos\OpenCL\Vendors'
+          if (-not (Test-Path $vendors)) {
+              # -Force creates the missing parent keys
+              New-Item -Path $vendors -Force | Out-Null
+          }
+          New-ItemProperty -Path $vendors -Name (Join-Path $oclcpu 'intelocl64.dll') `
+              -PropertyType DWord -Value 0 -Force | Out-Null
+          # the runtime directory on PATH also provides tbb12.dll
+          Add-Content -Path $env:GITHUB_ENV -Value "SYCL_BUNDLE_FOLDER=$root"
+          Add-Content -Path $env:GITHUB_PATH -Value $oclcpu
+          Add-Content -Path $env:GITHUB_PATH -Value (Join-Path $compiler 'bin')
+
+      - name: Setup Python
+        uses: actions/setup-python@6d4fd22b20465ccc0f7354476588e8df7c9ca0e0 # v7.1.0
+        with:
+          python-version: '3.15'
+          architecture: x64
+
+      - name: Create virtual environment
+        shell: pwsh
+        run: |
+          $ErrorActionPreference = 'Stop'
+          $PSNativeCommandUseErrorActionPreference = $true
+
+          $venv = Join-Path $env:RUNNER_TEMP 'venv'
+          python -m venv $venv
+          # dpctl adds <venv>\Library\bin to the DLL search path, so link it to
+          # the DPC++ runtime
+          New-Item -ItemType Directory -Path (Join-Path $venv 'Library') | Out-Null
+          New-Item -ItemType Junction -Path (Join-Path $venv 'Library\bin') `
+              -Target (Join-Path $env:SYCL_BUNDLE_FOLDER 'dpcpp_compiler\bin') | Out-Null
+          Add-Content -Path $env:GITHUB_ENV -Value "VIRTUAL_ENV=$venv"
+          Add-Content -Path $env:GITHUB_PATH -Value (Join-Path $venv 'Scripts')
+
+      - name: Install dpctl dependencies
+        shell: pwsh
+        run: |
+          $ErrorActionPreference = 'Stop'
+          $PSNativeCommandUseErrorActionPreference = $true
+          python -m pip install numpy cython "setuptools<80" pytest scikit-build cmake ninja "versioneer[toml]==0.29"
+
+      - name: Report compiler version
+        shell: pwsh
+        run: clang-cl --version
+
+      - name: Run sycl-ls
+        shell: pwsh
+        run: |
+          $ErrorActionPreference = 'Stop'
+          $PSNativeCommandUseErrorActionPreference = $true
+          $devices = sycl-ls
+          $devices
+          if (-not ($devices -match '^\[opencl:cpu\]')) {
+              sycl-ls --verbose
+              Write-Output '::error::no OpenCL CPU device found'
+              exit 1
+          }
+
+      - name: Build dpctl
+        shell: cmd
+        run: |
+          set "VSWHERE=%ProgramFiles(x86)%\Microsoft Visual Studio\Installer\vswhere.exe"
+          for /f "usebackq delims=" %%i in (`"%VSWHERE%" -latest -products * -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -property installationPath`) do set "VS_PATH=%%i"
+          if not defined VS_PATH (
+              echo ::error::Visual Studio with MSVC x64 tools not found
+              exit /b 1
+          )
+          call "%VS_PATH%\VC\Auxiliary\Build\vcvars64.bat" || exit /b 1
+          rem -fsycl links sycl9.lib, which the linker looks up on LIB
+          set "LIB=%SYCL_BUNDLE_FOLDER%\dpcpp_compiler\lib;%LIB%"
+          rem link.exe can't link the LTO bitcode pybind11 would otherwise build
+          python scripts\build_locally.py --c-compiler=clang-cl.exe --cxx-compiler=clang-cl.exe ^
+              --compiler-root="%SYCL_BUNDLE_FOLDER%\dpcpp_compiler\bin" ^
+              --cmake-opts="-DCMAKE_INTERPROCEDURAL_OPTIMIZATION=OFF" || exit /b 1
+
+      - name: Run lsplatforms
+        shell: pwsh
+        run: |
+          $ErrorActionPreference = 'Stop'
+          $PSNativeCommandUseErrorActionPreference = $true
+          python -m dpctl -f
+
+      - name: Run dpctl/tests
+        shell: pwsh
+        env:
+          SYCL_CACHE_PERSISTENT: 1
+        run: |
+          $ErrorActionPreference = 'Stop'
+          $PSNativeCommandUseErrorActionPreference = $true
+          python -m pytest -sv dpctl/tests
@@ -1,5 +1,11 @@
 cmake_minimum_required(VERSION 3.21...3.27 FATAL_ERROR)
 
+# link clang-cl targets through the compiler driver
+set(CMAKE_USER_MAKE_RULES_OVERRIDE_C
+    ${CMAKE_CURRENT_SOURCE_DIR}/cmake/WindowsClangClLinkRules.cmake)
+set(CMAKE_USER_MAKE_RULES_OVERRIDE_CXX
+    ${CMAKE_CURRENT_SOURCE_DIR}/cmake/WindowsClangClLinkRules.cmake)
+
 project(dpctl
     VERSION 0.24
     LANGUAGES CXX

@@ -0,0 +1,49 @@
+# CMake links clang-cl targets by calling the linker directly, so link options
+# such as -fsycl never reach the compiler driver. Link through the driver
+# instead, like Platform/Windows-IntelLLVM does for icx, passing linker flags
+# with -Xlinker (clang-cl drops -Wl, arguments).
+
+if(CMAKE_GENERATOR MATCHES "Visual Studio")
+  return()
+endif()
+
+foreach(_lang C CXX)
+  if(NOT CMAKE_${_lang}_COMPILER_ID STREQUAL "Clang"
+     OR NOT CMAKE_${_lang}_COMPILER_FRONTEND_VARIANT STREQUAL "MSVC"
+     OR CMAKE_${_lang}_LINK_MODE STREQUAL "DRIVER")
+    continue()
+  endif()
+
+  if(NOT _dpctl_clang_cl_linker_flags_wrapped)
+    set(_dpctl_clang_cl_linker_flags_wrapped TRUE)
+    foreach(_t EXE SHARED MODULE)
+      foreach(_cfg "" _DEBUG _RELEASE _RELWITHDEBINFO _MINSIZEREL)
+        set(_var CMAKE_${_t}_LINKER_FLAGS${_cfg}_INIT)
+        separate_arguments(_flags WINDOWS_COMMAND "${${_var}}")
+        list(TRANSFORM _flags PREPEND "-Xlinker ")
+        list(JOIN _flags " " ${_var})
+      endforeach()
+    endforeach()
+    set(CMAKE_LIBRARY_PATH_FLAG "-Xlinker /LIBPATH:")
+    set(CMAKE_LINK_DEF_FILE_FLAG "-Xlinker /DEF:")
+  endif()
+
+  set(CMAKE_${_lang}_LINK_MODE DRIVER)
+  set(CMAKE_${_lang}_LINKER_WRAPPER_FLAG "-Xlinker" " ")
+  unset(CMAKE_${_lang}_LINKER_WRAPPER_FLAG_SEP)
+  set(CMAKE_${_lang}_LINK_DEF_FILE_FLAG "-Xlinker /DEF:")
+  set(CMAKE_${_lang}_CREATE_WIN32_EXE "-Xlinker /subsystem:windows")
+  set(CMAKE_${_lang}_CREATE_CONSOLE_EXE "-Xlinker /subsystem:console")
+
+  set(CMAKE_${_lang}_LINK_EXECUTABLE
+    "${_CMAKE_VS_LINK_EXE}<CMAKE_${_lang}_COMPILER> ${CMAKE_CL_NOLOGO} <OBJECTS> ${CMAKE_START_TEMP_FILE} <LINK_FLAGS> <LINK_LIBRARIES> -link /out:<TARGET> /implib:<TARGET_IMPLIB> /pdb:<TARGET_PDB> /version:<TARGET_VERSION_MAJOR>.<TARGET_VERSION_MINOR>${_PLATFORM_LINK_FLAGS} ${CMAKE_END_TEMP_FILE}")
+  set(CMAKE_${_lang}_CREATE_SHARED_LIBRARY
+    "${_CMAKE_VS_LINK_DLL}<CMAKE_${_lang}_COMPILER> ${CMAKE_CL_NOLOGO} <OBJECTS> ${CMAKE_START_TEMP_FILE} -LD <LINK_FLAGS> <LINK_LIBRARIES> -link /out:<TARGET> /implib:<TARGET_IMPLIB> /pdb:<TARGET_PDB> /version:<TARGET_VERSION_MAJOR>.<TARGET_VERSION_MINOR>${_PLATFORM_LINK_FLAGS} ${CMAKE_END_TEMP_FILE}")
+  set(CMAKE_${_lang}_CREATE_SHARED_MODULE "${CMAKE_${_lang}_CREATE_SHARED_LIBRARY}")
+endforeach()
+
+unset(_lang)
+unset(_t)
+unset(_cfg)
+unset(_var)
+unset(_flags)
@@ -6,8 +6,14 @@ set(CYTHON_FLAGS "-t -w \"${CMAKE_SOURCE_DIR}\"")
 find_package(Cython REQUIRED)
 
 if(WIN32)
+    # clang-cl reads -Wall as /Wall, i.e. -Weverything
+    if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+        set(_dpctl_wall_flag "/W3 ")
+    else()
+        set(_dpctl_wall_flag "-Wall ")
+    endif()
     string(CONCAT WARNING_FLAGS
-        "-Wall "
+        "${_dpctl_wall_flag}"
         "-Wextra "
         "-Winit-self "
         "-Wunused-function "
@@ -35,7 +41,7 @@ if(WIN32)
         "${CMAKE_CXX_FLAGS_DEBUG} ${WARNING_FLAGS} ${SDL_FLAGS} -O1 -g1 -DDEBUG"
     )
     set(CMAKE_MODULE_LINKER_FLAGS_COVERAGE "${CMAKE_MODULE_LINKER_FLAGS_DEBUG}")
-    set(DPCTL_LDFLAGS "/NXCompat;/DynamicBase")
+    set(DPCTL_LDFLAGS "/NXCompat,/DynamicBase")
     mark_as_advanced(
         CMAKE_CXX_FLAGS_COVERAGE
         CMAKE_C_FLAGS_COVERAGE

@@ -181,8 +181,14 @@ configure_file(
 set(CMAKE_CXX_STANDARD 17)
 
 if(WIN32)
+    # clang-cl reads -Wall as /Wall, i.e. -Weverything
+    if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+        set(_dpctl_wall_flag "/W3 ")
+    else()
+        set(_dpctl_wall_flag "-Wall ")
+    endif()
     string(CONCAT WARNING_FLAGS
-        "-Wall "
+        "${_dpctl_wall_flag}"
         "-Wextra "
         "-Winit-self "
         "-Wunused-function "