title: Is there anything like a restrict keyword for C++ to indicate that _iterators_ are not aliased
body: <p>g++ does implement <code>__restrict__</code> for pointers, but I could not find anything about iterators. My overall intent is to encourage the compiler to vectorize stl loops.</p>
  <p><strong>Edit:</strong></p>
  <p>Even if the compiler is unable to vectorize, the <code>__restrict__</code> keyword should be able to tell the compiler that no unnecessary reloads are necessary inside a loop.</p>