Backport from trunk:

  Fix a potential 'SystemError: NULL result without error'.
  NULL may be a valid return value from PyLong_AsVoidPtr.
Also move an older ctypes NEWS item in the correct category.

Misc/NEWS

@@ -12,8 +12,6 @@ What's New in Python 2.5.2c1?
 Core and builtins
 -----------------
 
-- Prevent a segfault when a ctypes NULL function pointer is called.
-
 - Bug #1517: Possible segfault in lookup().
 
 - Issue #1638: %zd configure test fails on Linux.
@@ -171,6 +169,10 @@ Library
 Extension Modules
 -----------------
 
+- Fix a potential 'SystemError: NULL result without error' in _ctypes.
+
+- Prevent a segfault when a ctypes NULL function pointer is called.
+
 - Bug #1301: Bad assert in _tkinter fixed.
 
 - Patch #1114: fix curses module compilation on 64-bit AIX, & possibly

Modules/_ctypes/_ctypes.c

@@ -2896,7 +2896,7 @@ CFuncPtr_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 		|| PyLong_Check(PyTuple_GET_ITEM(args, 0)))) {
 		CDataObject *ob;
 		void *ptr = PyLong_AsVoidPtr(PyTuple_GET_ITEM(args, 0));
-		if (ptr == NULL)
+		if (ptr == NULL && PyErr_Occurred())
 			return NULL;
 		ob = (CDataObject *)GenericCData_new(type, args, kwds);
 		if (ob == NULL)