foo.cc: In function 'int main()':
foo.cc:34:23: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
     cout << x  << ' ' << y ;
     ~~~~~~~~~~~~~~~~~~^~~~
foo.cc:34:19: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
     cout << x  << ' ' << y ;
                   ^~~

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