/in/foo.cc: In function 'int main()':
/in/foo.cc:7:18: warning: 'x' is used uninitialized [-Wuninitialized]
    7 |         while(x1 < x)
      |               ~~~^~~
/in/foo.cc:5:13: note: 'x' was declared here
    5 |         int x;
      |             ^