title: gcc Optimization Flags - Do they really mean anything about the code written?
body: <p>I'm currently implementing a project in C in order to find shortest path between two nodes in a directed graph.
  I recently tried to use the -O3 optimization flag in compilation and I realized that it made the program much faster.</p>
  
  <p>Does that necessarily mean that the program has imperfections and generally a lot more room for code optimizations? Or does -O3 just make it more optimized no matter how good my code is?</p>