Address review comments

Author: markshannon

Include/internal/pycore_ceval.h

@@ -353,7 +353,7 @@ PyAPI_FUNC(_PyStackRef) _PyFloat_FromDouble_ConsumeInputs(_PyStackRef left, _PyS
 extern int _PyRunRemoteDebugger(PyThreadState *tstate);
 #endif
 
-_PyStackRef
+PyAPI_FUNC(_PyStackRef)
 _PyForIter_VirtualIteratorNext(PyThreadState* tstate, struct _PyInterpreterFrame* frame, _PyStackRef iter, _PyStackRef *index_ptr);
 
 #ifdef __cplusplus

Python/bytecodes.c

@@ -3130,6 +3130,7 @@ dummy_func(
                 if (PyStackRef_IsError(item)) {
                     ERROR_NO_POP();
                 }
+                // Jump forward by oparg and skip the following END_FOR
                 JUMPBY(oparg + 1);
                 DISPATCH();
             }
@@ -3159,6 +3160,7 @@ dummy_func(
                 if (PyStackRef_IsError(item)) {
                     ERROR_NO_POP();
                 }
+                // Jump forward by oparg and skip the following END_FOR
                 JUMPBY(oparg + 1);
                 DISPATCH();
             }

Python/ceval.c

@@ -3475,7 +3475,7 @@ _PyStackRef _PyForIter_VirtualIteratorNext(PyThreadState* tstate, _PyInterpreter
                 _PyErr_Clear(tstate);
             }
             else {
-                 return PyStackRef_ERROR;
+                return PyStackRef_ERROR;
             }
         }
         return PyStackRef_NULL;

Python/optimizer_bytecodes.c

@@ -843,7 +843,7 @@ dummy_func(void) {
     op(_GET_ITER, (iterable -- iter, index_or_null)) {
         if (sym_matches_type(iterable, &PyTuple_Type) || sym_matches_type(iterable, &PyList_Type)) {
             iter = iterable;
-            index_or_null = sym_new_type(ctx, &PyLong_Type);
+            index_or_null = sym_new_not_null(ctx);
         }
         else {
             iter = sym_new_not_null(ctx);