foo.c: In function 'main':
foo.c:4:15: warning: missing braces around initializer [-Wmissing-braces]
   int a[2][3]={1,2,3,4,5,6},n;
               ^
                {    }{    }
foo.c:17:8: warning: '*((void *)&a+24)[0]' is used uninitialized in this function [-Wuninitialized]
     sum+=*(p[i]);
     ~~~^~~~~~~~~
foo.c:4:7: note: '*((void *)&a+24)[0]' was declared here
   int a[2][3]={1,2,3,4,5,6},n;
       ^
foo.c:17:8: warning: '*((void *)&a+36)[0]' is used uninitialized in this function [-Wuninitialized]
     sum+=*(p[i]);
     ~~~^~~~~~~~~
foo.c:4:7: note: '*((void *)&a+36)[0]' was declared here
   int a[2][3]={1,2,3,4,5,6},n;
       ^

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