Fred's right -- we need PyList_SET_ITEM().

Doc/api.tex

@@ -1953,6 +1953,11 @@ Returns a new tuple object containing the contents of \var{list}.
 Macro form of \cfunction{PyList_GetItem()} without error checking.
 \end{cfuncdesc}
 
+\begin{cfuncdesc}{PyObject*}{PyList_SET_ITEM}{PyObject *list, int i,
+                                              PyObject *o}
+Macro form of \cfunction{PyList_SetItem()} without error checking.
+\end{cfuncdesc}
+
 \begin{cfuncdesc}{int}{PyList_GET_SIZE}{PyObject *list}
 Macro form of \cfunction{PyList_GetSize()} without error checking.
 \end{cfuncdesc}

Doc/api/api.tex

@@ -1953,6 +1953,11 @@ Returns a new tuple object containing the contents of \var{list}.
 Macro form of \cfunction{PyList_GetItem()} without error checking.
 \end{cfuncdesc}
 
+\begin{cfuncdesc}{PyObject*}{PyList_SET_ITEM}{PyObject *list, int i,
+                                              PyObject *o}
+Macro form of \cfunction{PyList_SetItem()} without error checking.
+\end{cfuncdesc}
+
 \begin{cfuncdesc}{int}{PyList_GET_SIZE}{PyObject *list}
 Macro form of \cfunction{PyList_GetSize()} without error checking.
 \end{cfuncdesc}

Include/listobject.h

@@ -74,6 +74,7 @@ extern PyObject *PyList_AsTuple Py_PROTO((PyObject *));
 
 /* Macro, trading safety for speed */
 #define PyList_GET_ITEM(op, i) (((PyListObject *)(op))->ob_item[i])
+#define PyList_SET_ITEM(op, i, v) (((PyListObject *)(op))->ob_item[i] = (v))
 #define PyList_GET_SIZE(op)    (((PyListObject *)(op))->ob_size)
 
 #ifdef __cplusplus

Python/bltinmodule.c

@@ -1282,7 +1282,7 @@ builtin_range(self, args)
 			Py_DECREF(v);
 			return NULL;
 		}
-		PyList_GET_ITEM(v, i) = w;
+		PyList_SET_ITEM(v, i, w);
 		ilow += istep;
 	}
 	return v;