foo.c: In function 'main':
foo.c:6:13: warning: unused variable 'b' [-Wunused-variable]
    6 |         int b[100000];
      |             ^
foo.c:20:21: warning: 'a' may be used uninitialized [-Wmaybe-uninitialized]
   20 |                 int m = a[1];
      |                     ^
foo.c:4:13: note: 'a' declared here
    4 |         int a[100000];
      |             ^

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