Index: immutables-0.15/tests/test_none_keys.py
===================================================================
--- immutables-0.15.orig/tests/test_none_keys.py
+++ immutables-0.15/tests/test_none_keys.py
@@ -1,8 +1,10 @@
 import unittest
+import sys
 
 from immutables.map import map_hash, map_mask, Map as PyMap
 from immutables._testutils import HashKey
 
+is_32bits = sys.maxsize <= 2**32  # 32bit-dness
 
 none_hash = map_hash(None)
 assert(none_hash != 1)
@@ -35,6 +37,8 @@ class NoneCollision(HashKey):
 class BaseNoneTest:
     Map = None
 
+    @unittest.skipIf(is_32bits,
+                     "fail on 32bit arch, gh#MagicStack/immutables#53")
     def test_none_collisions(self):
         collisions = [NoneCollision('a', level) for level in range(7)]
         indices = [map_mask(none_hash, shift) for shift in range(0, 32, 5)]