/in/foo.cc: In function 'int main()':
/in/foo.cc:25:8: warning: 'sum' may be used uninitialized in this function [-Wmaybe-uninitialized]
   sum+=s;
        ^
/in/foo.cc:25:8: warning: 's' may be used uninitialized in this function [-Wmaybe-uninitialized]