foo.c: In function 'main':
foo.c:6:10: warning: statement with no effect [-Wunused-value]
    6 |         x>=0;
      |         ~^~~
foo.c:7:10: warning: statement with no effect [-Wunused-value]
    7 |         y>=0;
      |         ~^~~
foo.c:6:10: warning: 'x' is used uninitialized [-Wuninitialized]
    6 |         x>=0;
      |         ~^~~
foo.c:5:13: note: 'x' declared here
    5 |         int x,y;
      |             ^
foo.c:7:10: warning: 'y' is used uninitialized [-Wuninitialized]
    7 |         y>=0;
      |         ~^~~
foo.c:5:15: note: 'y' declared here
    5 |         int x,y;
      |               ^

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