attempt at free-threaded support

Author: ngoldbaum

.github/workflows/ci.yml

@@ -22,7 +22,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12", "3.13", "3.14"]
+        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12", "3.13", "3.14", "3.14t"]
     steps:
       - name: Set git to use LF on Windows
         if: runner.os == 'Windows'
@@ -65,14 +65,18 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
+        python-version: [
+            ["3.x", "cp38-* pp*-*"],
+            ["3.14t", "cp314t-*"],
+        ]
 
     steps:
       - uses: actions/checkout@v5
         with:
           submodules: recursive
       - uses: actions/setup-python@v6
         with:
-          python-version: 3.x
+          python-version: ${{ matrix.python-version[0] }}
       - name: Install cibuildwheel
         run: python -m pip install cibuildwheel
       # - name: Install Visual C++ for Python 2.7
@@ -87,7 +91,7 @@ jobs:
       - name: Build wheels
         run: python -m cibuildwheel --output-dir wheelhouse
         env:
-          CIBW_BUILD: cp38-* pp*-*
+          CIBW_BUILD: ${{ matrix.python-version[1] }}
           CIBW_SKIP: "*musllinux*"
           CIBW_ENABLE: pypy
           CIBW_ARCHS_LINUX: auto aarch64

setup.py

@@ -3,6 +3,7 @@
 import re
 import platform
 import sys
+import sysconfig
 from setuptools import find_packages, setup
 from setuptools.command.build_ext import build_ext
 
@@ -74,11 +75,13 @@ def run(self):
     except ImportError:
         pass
     else:
-        class BDistWheel(wheel.bdist_wheel.bdist_wheel):
-            def finalize_options(self):
-                self.py_limited_api = "cp3{}".format(sys.version_info[1])
-                wheel.bdist_wheel.bdist_wheel.finalize_options(self)
-        cmdclass['bdist_wheel'] = BDistWheel
+        # the limited API is only supported on GIL builds as of Python 3.14
+        if not bool(sysconfig.get_config_var("Py_GIL_DISABLED")):
+            class BDistWheel(wheel.bdist_wheel.bdist_wheel):
+                def finalize_options(self):
+                    self.py_limited_api = "cp3{}".format(sys.version_info[1])
+                    wheel.bdist_wheel.bdist_wheel.finalize_options(self)
+            cmdclass['bdist_wheel'] = BDistWheel
 
 setup(
     name="brotlicffi",