commit 4a757609d131a29ef52eddcae108b7052e13d31b
author Benjamin Peterson <benjamin@python.org> Tue Sep 06 19:03:40 2016 -0700
committer Benjamin Peterson <benjamin@python.org> Tue Sep 06 19:03:40 2016 -0700
tree c5a1213b0ca4df58d45c5583df936a8ddd00e580
parent a1bc246dd5d86fc27fdcca708cf3eb2b2b803ac7

do not memcpy from NULL

Modules/hashtable.c

diff --git a/Modules/hashtable.c b/Modules/hashtable.c
index 133f313..fdddc19 100644
--- a/Modules/hashtable.c
+++ b/Modules/hashtable.c
@@ -327,7 +327,8 @@
     entry->key_hash = key_hash;
 
     assert(data_size == ht->data_size);
-    memcpy(_Py_HASHTABLE_ENTRY_DATA(entry), data, data_size);
+    if (data)
+        memcpy(_Py_HASHTABLE_ENTRY_DATA(entry), data, data_size);
 
     _Py_slist_prepend(&ht->buckets[index], (_Py_slist_item_t*)entry);
     ht->entries++;