bpo-40989: PyObject_INIT() becomes an alias to PyObject_Init() (GH-20901)

The PyObject_INIT() and PyObject_INIT_VAR() macros become aliases to,
respectively, PyObject_Init() and PyObject_InitVar() functions.

Rename _PyObject_INIT() and _PyObject_INIT_VAR() static inline
functions to, respectively, _PyObject_Init() and _PyObject_InitVar(),
and move them to pycore_object.h. Remove their return value:
their return type becomes void.

The _datetime module is now built with the Py_BUILD_CORE_MODULE macro
defined.

Remove an outdated comment on _Py_tracemalloc_config.

2 files changed, 31 insertions, 9 deletions

diff --git a/Include/internal/pycore_object.h b/Include/internal/pycore_object.h
index 32e86d0..14444a7 100644
--- a/Include/internal/pycore_object.h
+++ b/Include/internal/pycore_object.h
@@ -15,6 +15,37 @@ extern "C" {
 PyAPI_FUNC(int) _PyType_CheckConsistency(PyTypeObject *type);
 PyAPI_FUNC(int) _PyDict_CheckConsistency(PyObject *mp, int check_content);
 
+// Fast inlined version of PyType_HasFeature()
+static inline int
+_PyType_HasFeature(PyTypeObject *type, unsigned long feature) {
+    return ((type->tp_flags & feature) != 0);
+}
+
+/* Inline functions trading binary compatibility for speed:
+   _PyObject_Init() is the fast version of PyObject_Init(), and
+   _PyObject_InitVar() is the fast version of PyObject_InitVar().
+
+   These inline functions must not be called with op=NULL. */
+static inline void
+_PyObject_Init(PyObject *op, PyTypeObject *typeobj)
+{
+    assert(op != NULL);
+    Py_SET_TYPE(op, typeobj);
+    if (_PyType_HasFeature(typeobj, Py_TPFLAGS_HEAPTYPE)) {
+        Py_INCREF(typeobj);
+    }
+    _Py_NewReference(op);
+}
+
+static inline void
+_PyObject_InitVar(PyVarObject *op, PyTypeObject *typeobj, Py_ssize_t size)
+{
+    assert(op != NULL);
+    Py_SET_SIZE(op, size);
+    _PyObject_Init((PyObject *)op, typeobj);
+}
+
+
 /* Tell the GC to track this object.
  *
  * NB: While the object is tracked by the collector, it must be safe to call the
@@ -96,12 +127,6 @@ _PyObject_GET_WEAKREFS_LISTPTR(PyObject *op)
     return (PyObject **)((char *)op + offset);
 }
 
-// Fast inlined version of PyType_HasFeature()
-static inline int
-_PyType_HasFeature(PyTypeObject *type, unsigned long feature) {
-    return ((type->tp_flags & feature) != 0);
-}
-
 // Fast inlined version of PyObject_IS_GC()
 static inline int
 _PyObject_IS_GC(PyObject *obj)
diff --git a/Include/internal/pycore_pymem.h b/Include/internal/pycore_pymem.h
index 3d925e2..e4e35c1 100644
--- a/Include/internal/pycore_pymem.h
+++ b/Include/internal/pycore_pymem.h
@@ -69,9 +69,6 @@ PyAPI_FUNC(int) _PyMem_GetAllocatorName(
    PYMEM_ALLOCATOR_NOT_SET does nothing. */
 PyAPI_FUNC(int) _PyMem_SetupAllocators(PyMemAllocatorName allocator);
 
-/* bpo-35053: Expose _Py_tracemalloc_config for _Py_NewReference()
-   which access directly _Py_tracemalloc_config.tracing for best
-   performances. */
 struct _PyTraceMalloc_Config {
     /* Module initialized?
        Variable protected by the GIL */