title: How to specify new GCC path for CMake
body: <p>My OS is centos which has a default gcc in path <code>/usr/bin/gcc</code>. But it is old, I need a new version of gcc. So I install a new version in a new path <code>/usr/local/bin/gcc</code>.</p>
  
  <p>But when I run <code>cmake</code>, it still uses the old version gcc path(<code>/usr/bin/gcc</code>) . How can I specify the gcc to new path(<code>/usr/local/bin/gcc</code>).</p>
  
  <p>I have tried to overwrite <code>/usr/bin/gcc</code> with <code>/usr/local/bin/gcc</code>, but it not work.</p>