foo.c: In function 'main':
foo.c:7:12: warning: 'x1' is used uninitialized [-Wuninitialized]
    7 |         sum=x1+x2;
      |         ~~~^~~~~~
foo.c:5:9: note: 'x1' was declared here
    5 |     int x1,x2,sum,pro,rem;
      |         ^~
foo.c:7:12: warning: 'x2' is used uninitialized [-Wuninitialized]
    7 |         sum=x1+x2;
      |         ~~~^~~~~~
foo.c:5:12: note: 'x2' was declared here
    5 |     int x1,x2,sum,pro,rem;
      |            ^~

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