foo.cc: In function 'int main()':
foo.cc:12:26: warning: 'c' may be used uninitialized [-Wmaybe-uninitialized]
   12 |                         c++;
      |                         ~^~
foo.cc:5:21: note: 'c' was declared here
    5 |         int a[10],b,c,i;
      |                     ^