> I noticed when building with VC++ 2010 Express on the PGI/PGO
> builds that it warns about PGO not being available.

Even if PGO is not available, wrap_binaryfunc() and wrap_binaryfunc_l() functions get the same address when Python is compiled in "PGUpdate" mode. (I tried Visual C++ 2010 Express).

The issue was seen at least with the following versions:

Python 3.1.2 (r312:79149, Mar 21 2010, 00:41:52) [MSC v.1500 32 bit (Intel)] on win32
Python 3.2 (which version exactly?)
Python 3.3b.01, MSVC v16.00 64 bits (AMD 64) on win32

So the issue was also reproduced with old Python versions compiled with Visual C++ 2008, and I'm not sure that the "ICF" optimization is only enabled in "Profile-Guided" (PG*) modes.

If we choose to change Visual Studio options instead of changing the mode, we may also try /Gy- option:
http://msdn.microsoft.com/en-us/library/xsa71f43.aspx