foo.cc: In function 'int main()':
foo.cc:29:19: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout << x << ' ' << y;
  ~~~~~~~~~~~~~~~~~^~~~
foo.cc:29:15: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout << x << ' ' << y;
               ^~~

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