merging revision 75106 from trunk:
http://bugs.python.org/issue6836
A missing 'const' wasn't detected by Visual Studio.
diff --git a/Objects/obmalloc.c b/Objects/obmalloc.c
index b2c053f..9cf90c4 100644
--- a/Objects/obmalloc.c
+++ b/Objects/obmalloc.c
@@ -1369,7 +1369,7 @@
 	_PyObject_DebugFreeApi(_PYMALLOC_OBJ_ID, p);
 }
 void
-_PyObject_DebugCheckAddress(void *p)
+_PyObject_DebugCheckAddress(const void *p)
 {
 	_PyObject_DebugCheckAddressApi(_PYMALLOC_OBJ_ID, p);
 }