Fix a crasher where Python code managed to infinitely recurse in C code without ever going back out to Python code in PyObject_Call(). Required introducing a static RuntimeError instance so that normalizing an exception there is no reliance on a recursive call that would put the exception system over the recursion check itself.

--- a/Include/pyerrors.h	Fri Sep 07 03:17:50 2007 +0000
+++ b/Include/pyerrors.h	Fri Sep 07 04:18:30 2007 +0000
@@ -161,6 +161,7 @@
 #endif
 
 PyAPI_DATA(PyObject *) PyExc_MemoryErrorInst;
+PyAPI_DATA(PyObject *) PyExc_RecursionErrorInst;
 
 /* Predefined warning categories */
 PyAPI_DATA(PyObject *) PyExc_Warning;