[Pyrex] new null check

[Eric Huss]

A somewhat minor issue, I noticed that when creating a new object that it
was not checking for a NULL return.  Attached is a patch to add a check
(though I don't know if it is "correct", it seems to work for me).

-Eric
-------------- next part --------------
+++ Nodes.py	Thu Dec 15 21:50:51 2005
@@ -502,6 +502,7 @@
                 code.put_init_var_to_py_none(entry, "p->%s")
         entry = scope.lookup_here("__new__")
         if entry:
+            code.putln("if (o == 0) { return 0; }")
             code.putln(
                 "if (%s(o, a, k) < 0) {" % 
                     entry.func_cname)