foo.cc: In function ‘int main()’:
foo.cc:15:15: warning: ‘xx’ may be used uninitialized [-Wmaybe-uninitialized]
   15 |         cout<<xx<<endl;
      |               ^~
foo.cc:5:23: note: ‘xx’ was declared here
    5 |         int xmin,xmax,xx;
      |                       ^~