foo.c: In function 'main':
foo.c:6:11: warning: statement with no effect [-Wunused-value]
    6 |         y1==x1+x2;
      |         ~~^~~~~~~
foo.c:7:11: warning: statement with no effect [-Wunused-value]
    7 |         y2==x1*x2;
      |         ~~^~~~~~~
foo.c:8:11: warning: statement with no effect [-Wunused-value]
    8 |         y3==x1%x2;
      |         ~~^~~~~~~
foo.c:6:15: warning: 'x1' is used uninitialized [-Wuninitialized]
    6 |         y1==x1+x2;
      |             ~~^~~
foo.c:6:15: warning: 'x2' is used uninitialized [-Wuninitialized]

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