Python 3.14 on macOS requires MACOSX_DEPLOYMENT_TARGET set to 10.15

README.md

@@ -45,7 +45,7 @@ While cibuildwheel itself requires a recent Python version to run (we support th
 <sup>⁴ Experimental, not yet supported on PyPI, but can be used directly in web deployment. Use `--platform pyodide` to build.</sup><br>
 <sup>⁵ manylinux armv7l support is experimental. As there are no RHEL based image for this architecture, it's using an Ubuntu based image instead.</sup><br>
 
-- Builds manylinux, musllinux, macOS 10.9+ (10.13+ for Python 3.12+), and Windows wheels for CPython, PyPy, and GraalPy
+- Builds manylinux, musllinux, macOS, and Windows wheels for CPython, PyPy, and GraalPy
 - Works on GitHub Actions, Azure Pipelines, Travis CI, CircleCI, GitLab CI, and Cirrus CI
 - Bundles shared library dependencies on Linux and macOS through [auditwheel](https://github.com/pypa/auditwheel) and [delocate](https://github.com/matthew-brett/delocate)
 - Runs your library's tests against the wheel-installed version of your library

cibuildwheel/platforms/macos.py

@@ -289,8 +289,11 @@ def setup_python(
     # For arm64, the minimal deployment target is 11.0.
     # On x86_64 (or universal2), use 10.9 as a default.
     # CPython 3.12.6+ needs 10.13.
+    # CPython 3.14.0 needs 10.15.
     if config_is_arm64:
         default_target = "11.0"
+    elif Version(python_configuration.version) >= Version("3.14"):
+        default_target = "10.15"
     elif Version(python_configuration.version) >= Version("3.12"):
         default_target = "10.13"
     elif python_configuration.identifier.startswith("pp") and Version(

docs/platforms.md

@@ -63,7 +63,8 @@ macOS builds will honor the `MACOSX_DEPLOYMENT_TARGET` environment variable to c
 | Arch  | Python version range | Minimum target |
 |-------|----------------------|----------------|
 | Intel | CPython 3.8-3.11     | 10.9           |
-| Intel | CPython 3.12+        | 10.13          |
+| Intel | CPython 3.12-3.13    | 10.13          |
+| Intel | CPython 3.14+        | 10.15          |
 | AS    | CPython or PyPy      | 11             |
 | Intel | PyPy 3.8             | 10.13          |
 | Intel | PyPy 3.9+            | 10.15          |

test/utils.py

@@ -366,8 +366,10 @@ def _expected_wheels(
             elif python_abi_tag.startswith("cp"):
                 if python_abi_tag.startswith(("cp38", "cp39", "cp310", "cp311")):
                     min_macosx = macosx_deployment_target
-                else:
+                elif python_abi_tag.startswith(("cp312", "cp313")):
                     min_macosx = _floor_macosx(macosx_deployment_target, "10.13")
+                else:
+                    min_macosx = _floor_macosx(macosx_deployment_target, "10.15")
             elif python_abi_tag.startswith("graalpy"):
                 if python_abi_tag.startswith("graalpy311"):
                     min_macosx = macosx_deployment_target