64位gcc 编译32 程序

没试过，试一下   -m32:  
   
  These   -m   switches   are   supported   in   addition   to   the   above   on   AMD   x86-64   processors   in   64-bit   environments.    
   
  -m32,   -m64  
  Generate   code   for   a   32-bit   or   64-bit   environment.   The   32-bit   environment   sets   int,   long   and   pointer   to   32   bits   and   generates   code   that   runs   on   any   i386   system.   The   64-bit   environment   sets   int   to   32   bits   and   long   and   pointer   to   64   bits   and   generates   code   for   AMD's   x86-64   architecture.