/in/foo.c: In function 'main':
/in/foo.c:7:12: warning: format '%d' expects argument of type 'int', but argument 2 has type 'int *' [-Wformat=]
   printf("%d\n",&z);
            ^
/in/foo.c:5:6: warning: 'x' is used uninitialized in this function [-Wuninitialized]
   z=x*y;
     ~^~
/in/foo.c:5:6: warning: 'y' is used uninitialized in this function [-Wuninitialized]