title: How to printf uint64_t? Fails with: "spurious trailing ‘%’ in format"
body: <p>I wrote a very simple test code of printf uint64_t:</p>
  
  <pre><code>#include &lt;inttypes.h&gt;
  #include &lt;stdio.h&gt;
  
  int main()
  {
    uint64_t ui64 = 90;
    printf("test uint64_t : %" PRIu64 "\n", ui64);
    return 0;
  }
  </code></pre>
  
  <p>I use ubuntu 11.10 (64 bit) and gcc version 4.6.1 to compile it, but failed:</p>
  
  <pre><code>main.cpp: In function ‘int main()’:
  main.cpp:9:30: error: expected ‘)’ before ‘PRIu64’
  main.cpp:9:47: warning: spurious trailing ‘%’ in format [-Wformat]
  </code></pre>