I can reproduce this exclusively with the pgupdate build:

msbuild PCbuild\pcbuild.sln /p:Configuration=PGInstrument /p:Platform=win32
msbuild PCbuild\pcbuild.sln /p:Configuration=PGUpdate /p:Platform=win32

PCbuild\Win32-pgo\python.exe
Python 3.3.0b1 (default, Jul 30 2012, 23:45:42) [MSC v.1600 32 bit (Intel)] on win32                          
Type "help", "copyright", "credits" or "license" for more information.                                        
>>> from collections import namedtuple                                                                        
>>> foo = namedtuple('foo', '')                                                                               
>>> [1] + foo()                                                                                               
                                  

Interpreter exits silently here. So it could be either an optimizer
bug or it's a Python bug exposed by the optimizer making draconian
assumptions at the highest level (c.f. clang exposing overflows).