/in/foo.cc: In function 'int main()':
/in/foo.cc:15:18: warning: 'j' may be used uninitialized [-Wmaybe-uninitialized]
   15 |                 j=j+1;
      |                 ~^~~~
/in/foo.cc:12:13: note: 'j' was declared here
   12 |         int j;
      |             ^