Fix a bunch of compiler warnings.  In at least one case these were serious bugs!
diff --git a/Objects/listobject.c b/Objects/listobject.c
index 3d81656..9a11680 100644
--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -1979,7 +1979,7 @@
 		return 1;
 	if (!PyCFunction_Check(cmpfunc))
 		return 0;
-	f = (PyCFunction *)cmpfunc;
+	f = (PyCFunctionObject *)cmpfunc;
 	if (f->m_self != NULL)
 		return 0;
 	if (!PyString_Check(f->m_module))