foo.c: In function 'main':
foo.c:6:5: warning: 'i' is used uninitialized [-Wuninitialized]
    6 |     char ab[i];
      |     ^~~~
foo.c:5:19: note: 'i' was declared here
    5 |         short x,y,i,o;
      |                   ^
foo.c:8:17: warning: '*ab[<unknown>]' is used uninitialized [-Wuninitialized]
    8 |         while(ab[i]!='E'){
      |               ~~^~~
foo.c:18:18: warning: '*ab[0]' is used uninitialized [-Wuninitialized]
   18 |             if(ab[o]=='W')
      |                ~~^~~
foo.c:21:26: warning: 'y' may be used uninitialized [-Wmaybe-uninitialized]
   21 |                         y++;
      |                         ~^~
foo.c:5:17: note: 'y' was declared here
    5 |         short x,y,i,o;
      |                 ^
foo.c:19:26: warning: 'x' may be used uninitialized [-Wmaybe-uninitialized]
   19 |                         x++;
      |                         ~^~
foo.c:5:15: note: 'x' was declared here
    5 |         short x,y,i,o;
      |               ^

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