title: how gnu c++ implement new and delete
body: <p>I just see some declarations in libstdc++-v3, but can't find the definitions. Does the <code>new</code> and <code>delete</code> just encapsulate <code>malloc</code> and <code>free</code> ? Where can I find the definitions of <code>new</code> and <code>delete</code> ? And why can't I find the <code>bits/c++allocator.h</code> include in <code>bits/allocator.h</code> ? So many strange things in gcc.</p>