/in/foo.c: In function 'cmp_id':
/in/foo.c:50:20: warning: self-comparison always evaluates to false [-Wtautological-compare]
   return a->id_len < a->id_len ? 1 : 0;
                    ^
/in/foo.c: In function 'cmp_article_num':
/in/foo.c:59:21: warning: self-comparison always evaluates to false [-Wtautological-compare]
   if (a->article[i] != a->article[i]) {
                     ^~
/in/foo.c:66:23: warning: self-comparison always evaluates to false [-Wtautological-compare]
  return a->article[i] < a->article[i] ? 1: 0;
                       ^