diff -r 44253ce374fc Include/dictobject.h
--- a/Include/dictobject.h	Mon Jun 22 12:31:24 2015 -0400
+++ b/Include/dictobject.h	Tue Jun 23 01:21:45 2015 -0700
@@ -72,6 +72,10 @@
                                           PyObject *item, Py_hash_t hash);
 #endif
 PyAPI_FUNC(int) PyDict_DelItem(PyObject *mp, PyObject *key);
+#ifndef Py_LIMITED_API
+PyAPI_FUNC(int) _PyDict_DelItem_KnownHash(PyObject *mp, PyObject *key,
+                                          Py_hash_t hash);
+#endif
 PyAPI_FUNC(void) PyDict_Clear(PyObject *mp);
 PyAPI_FUNC(int) PyDict_Next(
     PyObject *mp, Py_ssize_t *pos, PyObject **key, PyObject **value);
diff -r 44253ce374fc Modules/_functoolsmodule.c
--- a/Modules/_functoolsmodule.c	Mon Jun 22 12:31:24 2015 -0400
+++ b/Modules/_functoolsmodule.c	Tue Jun 23 01:21:45 2015 -0700
@@ -601,6 +601,7 @@
 typedef struct lru_list_elem {
     PyObject_HEAD
     struct lru_list_elem *prev, *next;  /* borrowed links */
+    Py_hash_t hash;
     PyObject *key, *result;
 } lru_list_elem;
 
@@ -762,10 +763,14 @@
 infinite_lru_cache_wrapper(lru_cache_object *self, PyObject *args, PyObject *kwds)
 {
     PyObject *result;
+    Py_hash_t hash;
     PyObject *key = lru_cache_make_key(args, kwds, self->typed);
     if (!key)
         return NULL;
-    result = PyDict_GetItemWithError(self->cache, key);
+    hash = PyObject_Hash(key);
+    if (hash == -1)
+        return NULL;
+    result = _PyDict_GetItem_KnownHash(self->cache, key, hash);
     if (result) {
         Py_INCREF(result);
         self->hits++;
@@ -781,7 +786,7 @@
         Py_DECREF(key);
         return NULL;
     }
-    if (PyDict_SetItem(self->cache, key, result) < 0) {
+    if (_PyDict_SetItem_KnownHash(self->cache, key, result, hash) < 0) {
         Py_DECREF(result);
         Py_DECREF(key);
         return NULL;
@@ -813,11 +818,15 @@
 {
     lru_list_elem *link;
     PyObject *key, *result;
+    Py_hash_t hash;
 
     key = lru_cache_make_key(args, kwds, self->typed);
     if (!key)
         return NULL;
-    link  = (lru_list_elem *)PyDict_GetItemWithError(self->cache, key);
+    hash = PyObject_Hash(key);
+    if (hash == -1)
+        return NULL;
+    link  = (lru_list_elem *)_PyDict_GetItem_KnownHash(self->cache, key, hash);
     if (link) {
         lru_cache_extricate_link(link);
         lru_cache_append_link(self, link);
@@ -845,7 +854,8 @@
         /* Remove it from the cache.
            The cache dict holds one reference to the link,
            and the linked list holds yet one reference to it. */
-        if (PyDict_DelItem(self->cache, link->key) < 0) {
+        if (_PyDict_DelItem_KnownHash(self->cache, link->key,
+                                      link->hash) < 0) {
             lru_cache_append_link(self, link);
             Py_DECREF(key);
             Py_DECREF(result);
@@ -859,9 +869,11 @@
         oldkey = link->key;
         oldresult = link->result;
 
+        link->hash = hash;
         link->key = key;
         link->result = result;
-        if (PyDict_SetItem(self->cache, key, (PyObject *)link) < 0) {
+        if (_PyDict_SetItem_KnownHash(self->cache, key, (PyObject *)link,
+                                      hash) < 0) {
             Py_DECREF(link);
             Py_DECREF(oldkey);
             Py_DECREF(oldresult);
@@ -881,10 +893,12 @@
             return NULL;
         }
 
+        link->hash = hash;
         link->key = key;
         link->result = result;
         _PyObject_GC_TRACK(link);
-        if (PyDict_SetItem(self->cache, key, (PyObject *)link) < 0) {
+        if (_PyDict_SetItem_KnownHash(self->cache, key, (PyObject *)link,
+                                      hash) < 0) {
             Py_DECREF(link);
             return NULL;
         }
diff -r 44253ce374fc Objects/dictobject.c
--- a/Objects/dictobject.c	Mon Jun 22 12:31:24 2015 -0400
+++ b/Objects/dictobject.c	Tue Jun 23 01:21:45 2015 -0700
@@ -1242,33 +1242,20 @@
     }
     assert(key);
     assert(value);
+    assert(hash != -1);
     mp = (PyDictObject *)op;
 
     /* insertdict() handles any resizing that might be necessary */
     return insertdict(mp, key, hash, value);
 }
 
-int
-PyDict_DelItem(PyObject *op, PyObject *key)
+static int
+deldict(PyDictObject *mp, PyObject *key, Py_hash_t hash)
 {
-    PyDictObject *mp;
-    Py_hash_t hash;
     PyDictKeyEntry *ep;
     PyObject *old_key, *old_value;
     PyObject **value_addr;
 
-    if (!PyDict_Check(op)) {
-        PyErr_BadInternalCall();
-        return -1;
-    }
-    assert(key);
-    if (!PyUnicode_CheckExact(key) ||
-        (hash = ((PyASCIIObject *) key)->hash) == -1) {
-        hash = PyObject_Hash(key);
-        if (hash == -1)
-            return -1;
-    }
-    mp = (PyDictObject *)op;
     ep = (mp->ma_keys->dk_lookup)(mp, key, hash, &value_addr);
     if (ep == NULL)
         return -1;
@@ -1290,6 +1277,37 @@
     return 0;
 }
 
+int
+PyDict_DelItem(PyObject *op, PyObject *key)
+{
+    Py_hash_t hash;
+
+    if (!PyDict_Check(op)) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+    assert(key);
+    if (!PyUnicode_CheckExact(key) ||
+        (hash = ((PyASCIIObject *) key)->hash) == -1) {
+        hash = PyObject_Hash(key);
+        if (hash == -1)
+            return -1;
+    }
+    return deldict((PyDictObject *)op, key, hash);
+}
+
+int
+_PyDict_DelItem_KnownHash(PyObject *op, PyObject *key, Py_hash_t hash)
+{
+    if (!PyDict_Check(op)) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+    assert(key);
+    assert(hash != -1);
+    return deldict((PyDictObject *)op, key, hash);
+}
+
 void
 PyDict_Clear(PyObject *op)
 {