GH-127705: Use _PyStackRefs in the default build.

Include/internal/pycore_ceval.h

@@ -325,7 +325,7 @@ _Py_eval_breaker_bit_is_set(PyThreadState *tstate, uintptr_t bit)
 void _Py_set_eval_breaker_bit_all(PyInterpreterState *interp, uintptr_t bit);
 void _Py_unset_eval_breaker_bit_all(PyInterpreterState *interp, uintptr_t bit);
 
-PyAPI_FUNC(PyObject *) _PyFloat_FromDouble_ConsumeInputs(_PyStackRef left, _PyStackRef right, double value);
+PyAPI_FUNC(_PyStackRef) _PyFloat_FromDouble_ConsumeInputs(_PyStackRef left, _PyStackRef right, double value);
 
 
 #ifdef __cplusplus

Include/internal/pycore_frame.h

@@ -142,17 +142,23 @@ _PyFrame_NumSlotsForCodeObject(PyCodeObject *code)
 
 static inline void _PyFrame_Copy(_PyInterpreterFrame *src, _PyInterpreterFrame *dest)
 {
-    *dest = *src;
+    dest->f_executable = PyStackRef_MakeHeapSafe(src->f_executable);
+    // Don't leave a dangling pointer to the old frame when creating generators
+    // and coroutines:
+    dest->previous = NULL;
+    dest->f_funcobj = PyStackRef_MakeHeapSafe(src->f_funcobj);
+    dest->f_globals = src->f_globals;
+    dest->f_builtins = src->f_builtins;
+    dest->f_locals = src->f_locals;
+    dest->frame_obj = src->frame_obj;
+    dest->instr_ptr = src->instr_ptr;
     assert(src->stackpointer != NULL);
     int stacktop = (int)(src->stackpointer - src->localsplus);
-    assert(stacktop >= _PyFrame_GetCode(src)->co_nlocalsplus);
+    assert(stacktop >= 0);
     dest->stackpointer = dest->localsplus + stacktop;
-    for (int i = 1; i < stacktop; i++) {
-        dest->localsplus[i] = src->localsplus[i];
+    for (int i = 0; i < stacktop; i++) {
+        dest->localsplus[i] = PyStackRef_MakeHeapSafe(src->localsplus[i]);
     }
-    // Don't leave a dangling pointer to the old frame when creating generators
-    // and coroutines:
-    dest->previous = NULL;
 
 #ifdef Py_GIL_DISABLED
     PyCodeObject *co = _PyFrame_GetCode(dest);
@@ -405,7 +411,7 @@ _PyFrame_PushTrampolineUnchecked(PyThreadState *tstate, PyCodeObject *code, int
 
 PyAPI_FUNC(_PyInterpreterFrame *)
 _PyEvalFramePushAndInit(PyThreadState *tstate, _PyStackRef func,
-                        PyObject *locals, _PyStackRef const* args,
+                        PyObject *locals, _PyStackRef const *args,
                         size_t argcount, PyObject *kwnames,
                         _PyInterpreterFrame *previous);
 

Include/internal/pycore_long.h

@@ -111,7 +111,7 @@ PyAPI_DATA(PyObject*) _PyLong_Rshift(PyObject *, int64_t);
 // Export for 'math' shared extension
 PyAPI_DATA(PyObject*) _PyLong_Lshift(PyObject *, int64_t);
 
-PyAPI_FUNC(PyObject*) _PyLong_Add(PyLongObject *left, PyLongObject *right);
+PyAPI_FUNC(_PyStackRef) _PyLong_Add(PyLongObject *left, PyLongObject *right);
 PyAPI_FUNC(PyObject*) _PyLong_Multiply(PyLongObject *left, PyLongObject *right);
 PyAPI_FUNC(PyObject*) _PyLong_Subtract(PyLongObject *left, PyLongObject *right);