title: gcc: Reduce libc required version
body: <p>I am trying to run a newly compiled binary on some oldish 32bits RedHat distribution.<br>
  The binary is compiled C (not++) on a CentOS 32bits VM running libc v2.12.<br>
  <br>
  RedHat complains about libc version: <pre>error while loading shared libraries: requires glibc 2.5 or later dynamic linker</pre>
  Since my program is rather simplistic, It is most likely not using anything new from libc.<br>
  <br>
  <strong>Is there a way to reduce libc version requirement</strong></p>