title: Install gcc49 via homebrew failed
body: <p>I am trying to install gcc49 via homebrew.</p>
  
  <p>I give a command like:</p>
  
  <pre><code>brew install gcc49
  </code></pre>
  
  <p>but it is stuck at</p>
  
  <pre><code>==&gt; ../configure --build=x86_64-apple-darwin13.0.2 --prefix=/usr/local/Cellar/gc
  ==&gt; make bootstrap
  </code></pre>