Update weakref_ops.py

Author: BobTheBuidler

mypyc/primitives/weakref_ops.py

@@ -1,3 +1,4 @@
+from mypyc.ir.ops import ERR_MAGIC
 from mypyc.ir.rtypes import object_rprimitive
 from mypyc.primitives.registry import function_op
 
@@ -8,11 +9,13 @@
     arg_types=[object_rprimitive, object_rprimitive],
     return_type=object_rprimitive,
     c_function_name="PyWeakref_NewRef",
+    error_kind=ERR_MAGIC,
 )
 
 py_weakref_new_ref_op = function_op(
     name="weakref.proxy",
     arg_types=[object_rprimitive, object_rprimitive],
     return_type=object_rprimitive,
     c_function_name="PyWeakref_NewProxy",
+    error_kind=ERR_MAGIC,
 )