title: How can I change the default seed in std::hash<>?
body: <p>I learn from <a href="https://stackoverflow.com/questions/19411742/what-is-the-default-hash-function-used-in-c-stdunordered-map">this problem</a> that the default hash function used in <code>std::unordered_map</code> is murmurhash2.</p>
  
  <pre><code>// This file defines Hash_bytes, a primitive used for defining hash
  // functions. Based on public domain MurmurHashUnaligned2, by Austin
  // Appleby.  http://murmurhash.googlepages.com/
  </code></pre>
  
  <p>My problem is how can I change the default seed of that hash function, as a constant hash seed is prone to be hacked.</p>
  
  <p>p.s. I know I can use my own hash factor with <code>unordered_map</code>. But my question is about the seed of builtin hash function of C++11.</p>