/in/foo.c: In function 'main':
/in/foo.c:13:4: warning: 's' may be used uninitialized in this function [-Wmaybe-uninitialized]
   x=x*y/gcd(x,y);
   ~^~~~~~~~~~~~~
/in/foo.c: In function 'gcd':
/in/foo.c:30:9: warning: 's' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return s;
         ^