Fix misaligned access.

memory.c

@@ -4,8 +4,7 @@
  * Copyright 2014      Lucas Jones <https://github.com/lucasjones>
  * Copyright 2014-2016 Wolf9466    <https://github.com/OhGodAPet>
  * Copyright 2016      Jay D Dee   <jayddee246@gmail.com>
- * Copyright 2016-2017 XMRig       <support@xmrig.com>
- *
+ * Copyright 2016-2018 XMRig       <support@xmrig.com>
  *
  *   This program is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -31,6 +30,8 @@ static size_t offset = 0;
 
 
 void * persistent_calloc(size_t num, size_t size) {
+    size += size % 16;
+
     void *mem = &persistent_memory[offset];
     offset += (num * size);