/in/foo.cc: In function 'int main()':
/in/foo.cc:28:7: warning: unused variable 'x' [-Wunused-variable]
   int x;
       ^
/in/foo.cc:30:7: warning: unused variable 'y' [-Wunused-variable]
   int y;
       ^
/in/foo.cc:32:7: warning: unused variable 'z' [-Wunused-variable]
   int z;
       ^