gh-105387: Limited C API implements Py_INCREF() as func

In the limited C API version 3.12 and newer, Py_INCREF() and
Py_DECREF() functions are now implemented as opaque function calls in
the stable ABI to hide implementation details.

Author: vstinner

Include/object.h

@@ -610,8 +610,9 @@ PyAPI_FUNC(void) _Py_DecRef(PyObject *);
 
 static inline Py_ALWAYS_INLINE void Py_INCREF(PyObject *op)
 {
-#if defined(Py_REF_DEBUG) && defined(Py_LIMITED_API)
-    // Stable ABI for Python built in debug mode
+#if defined(Py_LIMITED_API) && (Py_LIMITED_API+0 >= 0x030c0000 || defined(Py_REF_DEBUG))
+    // Stable ABI implements Py_INCREF() as a function call on limited C API
+    // version 3.12 and newer, and on Python built in debug mode
     _Py_IncRef(op);
 #else
     // Non-limited C API and limited C API for Python 3.9 and older access
@@ -641,8 +642,9 @@ static inline Py_ALWAYS_INLINE void Py_INCREF(PyObject *op)
 #  define Py_INCREF(op) Py_INCREF(_PyObject_CAST(op))
 #endif
 
-#if defined(Py_REF_DEBUG) && defined(Py_LIMITED_API)
-// Stable ABI for Python built in debug mode
+#if defined(Py_LIMITED_API) && (Py_LIMITED_API+0 >= 0x030c0000 || defined(Py_REF_DEBUG))
+// Stable ABI implements Py_DECREF() as a function call on limited C API
+// version 3.12 and newer, and on Python built in debug mode
 static inline void Py_DECREF(PyObject *op) {
     _Py_DecRef(op);
 }