/in/foo.cc: In function 'bool hw(int)':
/in/foo.cc:12:2: warning: 'b' may be used uninitialized in this function [-Wmaybe-uninitialized]
  if(x==b)
  ^~
/in/foo.cc: In function 'int main()':
/in/foo.cc:12:2: warning: 'b' may be used uninitialized in this function [-Wmaybe-uninitialized]
  if(x==b)
  ^~
/in/foo.cc:6:6: note: 'b' was declared here
  int b;
      ^