Patch #1675981: remove unreachable code from type.__new__() method.

__dict__ and __weakref__ are removed from the slots tuple earlier
in the code, in the loop that mangles slot names.
 (backport from rev. 54270)

Misc/NEWS

@@ -12,6 +12,8 @@ What's New in Python 2.5.1c1?
 Core and builtins
 -----------------
 
+- Patch #1675981: remove unreachable code from ``type.__new__()`` method.
+
 - Patch #1638879: don't accept strings with embedded NUL bytes in long().
 
 - Bug #1674503: close the file opened by execfile() in an error condition.

Objects/typeobject.c

@@ -1935,13 +1935,11 @@ type_new(PyTypeObject *metatype, PyObject *args, PyObject *kwds)
 				PyTuple_GET_ITEM(slots, i));
 			mp->type = T_OBJECT_EX;
 			mp->offset = slotoffset;
-			if (base->tp_weaklistoffset == 0 &&
-			    strcmp(mp->name, "__weakref__") == 0) {
-				add_weak++;
-				mp->type = T_OBJECT;
-				mp->flags = READONLY;
-				type->tp_weaklistoffset = slotoffset;
-			}
+
+			/* __dict__ and __weakref__ are already filtered out */
+			assert(strcmp(mp->name, "__dict__") != 0);
+			assert(strcmp(mp->name, "__weakref__") != 0);
+
 			slotoffset += sizeof(PyObject *);
 		}
 	}