diff -r 9e8e15993aae Modules/_datetimemodule.c
--- a/Modules/_datetimemodule.c	Tue Sep 13 20:48:13 2016 +0200
+++ b/Modules/_datetimemodule.c	Tue Sep 13 21:43:12 2016 -0700
@@ -2834,21 +2834,19 @@
     return clone;
 }
 
-static Py_hash_t
-generic_hash(unsigned char *data, int len)
-{
-    return _Py_HashBytes(data, len);
-}
-
-
 static PyObject *date_getstate(PyDateTime_Date *self);
 
 static Py_hash_t
 date_hash(PyDateTime_Date *self)
 {
     if (self->hashcode == -1) {
-        self->hashcode = generic_hash(
-            (unsigned char *)self->data, _PyDateTime_DATE_DATASIZE);
+        // Force the 8-byte alignment required by _Py_HashBytes.
+        union {
+            unsigned char bytes[sizeof(self->data)];
+            uint64_t dummy;
+        } data;
+        memcpy(data.bytes, self->data, sizeof(self->data));
+        self->hashcode = _Py_HashBytes(data.bytes, sizeof(self->data));
     }
 
     return self->hashcode;
@@ -3883,9 +3881,15 @@
             return -1;
 
         /* Reduce this to a hash of another object. */
-        if (offset == Py_None)
-            self->hashcode = generic_hash(
-                (unsigned char *)self->data, _PyDateTime_TIME_DATASIZE);
+        if (offset == Py_None) {
+            // Force the 8-byte alignment required by _Py_HashBytes.
+            union {
+                unsigned char bytes[sizeof(self->data)];
+                uint64_t dummy;
+            } data;
+            memcpy(data.bytes, self->data, sizeof(self->data));
+            self->hashcode = _Py_HashBytes(data.bytes, sizeof(self->data));
+        }
         else {
             PyObject *temp1, *temp2;
             int seconds, microseconds;
@@ -4959,9 +4963,15 @@
             return -1;
 
         /* Reduce this to a hash of another object. */
-        if (offset == Py_None)
-            self->hashcode = generic_hash(
-                (unsigned char *)self->data, _PyDateTime_DATETIME_DATASIZE);
+        if (offset == Py_None) {
+            // Force the 8-byte alignment required by _Py_HashBytes.
+            union {
+                unsigned char bytes[sizeof(self->data)];
+                uint64_t dummy;
+            } data;
+            memcpy(data.bytes, self->data, sizeof(self->data));
+            self->hashcode = _Py_HashBytes(data.bytes, sizeof(self->data));
+        }
         else {
             PyObject *temp1, *temp2;
             int days, seconds;
diff -r 9e8e15993aae Objects/memoryobject.c
--- a/Objects/memoryobject.c	Tue Sep 13 20:48:13 2016 +0200
+++ b/Objects/memoryobject.c	Tue Sep 13 21:43:12 2016 -0700
@@ -2851,7 +2851,8 @@
             return -1;
         }
 
-        if (!MV_C_CONTIGUOUS(self->flags)) {
+        // _Py_HashBytes requires a 8-byte-aligned contiguous buffer.
+        if (!MV_C_CONTIGUOUS(self->flags) || ((uintptr_t)mem & 0x7) != 0) {
             mem = PyMem_Malloc(view->len);
             if (mem == NULL) {
                 PyErr_NoMemory();
diff -r 9e8e15993aae Python/pyhash.c
--- a/Python/pyhash.c	Tue Sep 13 20:48:13 2016 +0200
+++ b/Python/pyhash.c	Tue Sep 13 21:43:12 2016 -0700
@@ -154,6 +154,9 @@
         return 0;
     }
 
+    // 8-byte alignment is required.
+    assert(((uintptr_t)src & 0x7) == 0);
+
 #ifdef Py_HASH_STATS
     hashstats[(len <= Py_HASH_STATS_MAX) ? len : 0]++;
 #endif