Bug in large literal indexing.

tests/run/index.pyx

@@ -126,3 +126,9 @@ def test_boundscheck(list L, tuple t, object o, unsigned long ix):
     IndexError: string index out of range
     """
     return L[ix], t[ix], o[ix]
+
+def large_literal_index(object o):
+    """
+    >>> large_literal_index({1000000000000000000000000000000: "yes"})
+    """
+    return o[1000000000000000000000000000000]