Python 3.2 introduced the *Limited API*, a subset of Python's C API.
Extensions that only use the Limited API can be
-compiled once and work with multiple versions of Python.
+compiled once and be loaded on multiple versions of Python.
Contents of the Limited API are :ref:`listed below <limited-api-list>`.
.. c:macro:: Py_LIMITED_API
Define ``Py_LIMITED_API`` to the value of :c:macro:`PY_VERSION_HEX`
corresponding to the lowest Python version your extension supports.
- The extension will work without recompilation with all Python 3 releases
+ The extension will be ABI-compatible with all Python 3 releases
from the specified one onward, and can use Limited API introduced up to that
version.
----------
To enable this, Python provides a *Stable ABI*: a set of symbols that will
-remain compatible across Python 3.x versions.
+remain ABI-compatible across Python 3.x versions.
+
+.. note::
+
+ The Stable ABI prevents ABI issues, like linker errors due to missing
+ symbols or data corruption due to changes in structure layouts or function
+ signatures.
+ However, other changes in Python can change the *behavior* of extensions.
+ See Python's Backwards Compatibility Policy (:pep:`387`) for details.
The Stable ABI contains symbols exposed in the :ref:`Limited API
<limited-c-api>`, but also other ones – for example, functions necessary to