Remove anonymous union from PyObject

Author: eduardo-elizondo

Include/Python.h

@@ -16,14 +16,13 @@
 #  define _SGI_MP_SOURCE
 #endif
 
-// stdlib.h, stdio.h, errno.h and string.h headers are not used by Python
+// stdlib.h, stdio.h, and errno.h headers are not used by Python
 // headers, but kept for backward compatibility. They are excluded from the
 // limited C API of Python 3.11.
 #if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
 #  include <stdlib.h>
 #  include <stdio.h>              // FILE*
 #  include <errno.h>              // errno
-#  include <string.h>             // memcpy()
 #endif
 #ifndef MS_WINDOWS
 #  include <unistd.h>
@@ -34,6 +33,7 @@
 
 #include <assert.h>               // assert()
 #include <wchar.h>                // wchar_t
+#include <string.h>               // memcpy()
 
 #include "pyport.h"
 #include "pymacro.h"

Include/object.h

@@ -131,14 +131,14 @@ check by comparing the reference count field to the immortality reference count.
 #define PyObject_HEAD_INIT(type)    \
     {                               \
         _PyObject_EXTRA_INIT        \
-        { _Py_IMMORTAL_REFCNT },    \
+        _Py_IMMORTAL_REFCNT,        \
         (type)                      \
     },
 #else
 #define PyObject_HEAD_INIT(type) \
     {                            \
         _PyObject_EXTRA_INIT     \
-        { 1 },                   \
+        1,                       \
         (type)                   \
     },
 #endif /* Py_BUILD_CORE */
@@ -165,12 +165,7 @@ check by comparing the reference count field to the immortality reference count.
  */
 struct _object {
     _PyObject_HEAD_EXTRA
-    union {
-       Py_ssize_t ob_refcnt;
-#if SIZEOF_VOID_P > 4
-       PY_UINT32_T ob_refcnt_split[2];
-#endif
-    };
+    Py_ssize_t ob_refcnt;
     PyTypeObject *ob_type;
 };
 
@@ -624,12 +619,12 @@ static inline Py_ALWAYS_INLINE void Py_INCREF(PyObject *op)
     // directly PyObject.ob_refcnt.
 #if SIZEOF_VOID_P > 4
     // Portable saturated add, branching on the carry flag and set low bits
-    PY_UINT32_T cur_refcnt = op->ob_refcnt_split[PY_BIG_ENDIAN];
+    PY_UINT32_T cur_refcnt = _Py_CAST(PY_UINT32_T, op->ob_refcnt);
     PY_UINT32_T new_refcnt = cur_refcnt + 1;
     if (new_refcnt == 0) {
         return;
     }
-    op->ob_refcnt_split[PY_BIG_ENDIAN] = new_refcnt;
+    memcpy(&op->ob_refcnt, &new_refcnt, sizeof(new_refcnt));
 #else
     // Explicitly check immortality against the immortal value
     if (_Py_IsImmortal(op)) {

Objects/object.c

@@ -1876,7 +1876,7 @@ PyTypeObject _PyNone_Type = {
 
 PyObject _Py_NoneStruct = {
     _PyObject_EXTRA_INIT
-    { _Py_IMMORTAL_REFCNT },
+    _Py_IMMORTAL_REFCNT,
     &_PyNone_Type
 };
 
@@ -1979,7 +1979,7 @@ PyTypeObject _PyNotImplemented_Type = {
 
 PyObject _Py_NotImplementedStruct = {
     _PyObject_EXTRA_INIT
-    { _Py_IMMORTAL_REFCNT },
+    _Py_IMMORTAL_REFCNT,
     &_PyNotImplemented_Type
 };
 

Objects/setobject.c

@@ -2544,6 +2544,6 @@ static PyTypeObject _PySetDummy_Type = {
 
 static PyObject _dummy_struct = {
     _PyObject_EXTRA_INIT
-    { _Py_IMMORTAL_REFCNT },
+    _Py_IMMORTAL_REFCNT,
     &_PySetDummy_Type
 };

Objects/sliceobject.c

@@ -99,7 +99,7 @@ PyTypeObject PyEllipsis_Type = {
 
 PyObject _Py_EllipsisObject = {
     _PyObject_EXTRA_INIT
-    { _Py_IMMORTAL_REFCNT },
+    _Py_IMMORTAL_REFCNT,
     &PyEllipsis_Type
 };