diff options
| -rw-r--r-- | Objects/setobject.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/Objects/setobject.c b/Objects/setobject.c index 8de0419..47415e6 100644 --- a/Objects/setobject.c +++ b/Objects/setobject.c @@ -663,20 +663,22 @@ frozenset_hash(PyObject *self) PySetObject *so = (PySetObject *)self; PyObject *key, *value; int pos = 0; - long hash = 1905176217L; + long hash = 1927868237L; if (so->hash != -1) return so->hash; + hash *= (PyDict_Size(so->data) + 1); while (PyDict_Next(so->data, &pos, &key, &value)) { - /* Multiplying by a large prime increases the bit dispersion for - closely spaced hash values. The is important because some - use cases have many combinations of a small number of - elements with nearby hashes so that many distinct combinations - collapse to only a handful of distinct hash values. */ - hash ^= PyObject_Hash(key) * 3644798167u; + /* Work to increase the bit dispersion for closely spaced hash + values. The is important because some use cases have many + combinations of a small number of elements with nearby + hashes so that many distinct combinations collapse to only + a handful of distinct hash values. */ + long h = PyObject_Hash(key); + hash ^= (h ^ (h << 16) ^ 89869747L) * 3644798167u; } - hash *= 69069L; + hash = hash * 69069L + 907133923L; if (hash == -1) hash = 590923713L; so->hash = hash; |