/in/foo.cc: In function 'int main()':
/in/foo.cc:29:9: warning: 's' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return s;
         ^
/in/foo.cc:26:16: note: 's' was declared here
  long long int s;
                ^
/in/foo.cc: In function 'int sum(int, int, int*)':
/in/foo.cc:29:9: warning: 's' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return s;
         ^