foo.c: In function 'main':
foo.c:8:11: warning: statement with no effect [-Wunused-value]
    8 |         d1<=d2;
      |         ~~^~~~
foo.c:6:13: warning: 'a' is used uninitialized [-Wuninitialized]
    6 |         d1=a*10+b;
      |            ~^~~
foo.c:6:11: warning: 'b' is used uninitialized [-Wuninitialized]
    6 |         d1=a*10+b;
      |         ~~^~~~~~~
foo.c:7:13: warning: 'c' is used uninitialized [-Wuninitialized]
    7 |         d2=c*10+d;
      |            ~^~~
foo.c:7:11: warning: 'd' is used uninitialized [-Wuninitialized]
    7 |         d2=c*10+d;
      |         ~~^~~~~~~

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