title: How to compile a C++ program as 64-bit on 64-bit machine?
body: <p>Perhaps a very trivial question:</p>
  
  <p>I need to compile a program as 64-bit (earlier makefile written to compile it as 32-bit).</p>
  
  <p>I saw the option -m32 appearing in command line parameters with each file compilation. So, I modified the makefile to get rid of -m32 in OPTFLAG , but again when the program compiles, I still see -m32 showing up and binaries are still 32-bit. Does this m32 come from somewhere else as well?</p>