Build wheels for arm64 Windows

.github/workflows/wheel.yml

@@ -104,6 +104,10 @@ jobs:
         arch:
           - 'x86'
           - 'x64'
+          - 'arm64'
+        exclude:
+          - py: '3.8'
+            arch: 'arm64'
     runs-on: 'windows-2022'
     env:
       ZSTD_WARNINGS_AS_ERRORS: '1'
@@ -112,14 +116,25 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.py }}
-          architecture: ${{ matrix.arch }}
+          architecture: ${{ matrix.arch == 'arm64' && 'x64' || matrix.arch }}
 
       - uses: actions/checkout@v4
 
       - name: Build Wheel
+        if: matrix.arch != 'arm64'
         run: |
           python -m pip wheel -w dist .
 
+      - name: Build Wheel
+        if: matrix.arch == 'arm64'
+        shell: bash
+        run: |
+          python -m pip install cibuildwheel
+          export CIBW_ARCHS=ARM64
+          export CIBW_BUILD=cp$(echo ${{ matrix.py }} | tr -d .)-*
+          export CIBW_BUILD_VERBOSITY=1
+          cibuildwheel --output-dir dist --arch ARM64
+
       - name: Upload Wheel
         uses: actions/upload-artifact@v4
         with:

setup.py

@@ -34,6 +34,27 @@
 if sys.version_info[0:2] >= (3, 13):
     MINIMUM_CFFI_VERSION = "1.17"
 
+ext_suffix = os.environ.get("SETUPTOOLS_EXT_SUFFIX")
+if ext_suffix:
+    import sysconfig
+    # setuptools._distutils.command.build_ext doesn't use
+    # SETUPTOOLS_EXT_SUFFIX like setuptools.command.build_ext does.
+    # Work around the issue so that cross-compilation can work
+    # properly.
+    sysconfig.get_config_vars()["EXT_SUFFIX"] = ext_suffix
+    try:
+        # Older versions of python didn't have EXT_SUFFIX, and setuptools
+        # sets its own value, but since we've already set one, we don't
+        # want setuptools to overwrite it.
+        import setuptools._distutils.compat.py39 as py39compat
+    except ImportError:
+        try:
+            import setuptools._distutils.py39compat as py39compat
+        except ImportError:
+            pass
+    if py39compat:
+        py39compat.add_ext_suffix = lambda vars: None
+
 try:
     import cffi