/in/isSibling.c: In function 'isSibling':
/in/isSibling.c:13:9: warning: passing argument 1 of 'qsort' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
  qsort (phrase1, len1, sizeof(char*),cmp_str_size);
         ^~~~~~~
In file included from /in/isSibling.c:2:0:
/usr/include/stdlib.h:827:13: note: expected 'void *' but argument is of type 'const char *'
 extern void qsort (void *__base, size_t __nmemb, size_t __size,
             ^~~~~
/in/isSibling.c:14:9: warning: passing argument 1 of 'qsort' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
  qsort (phrase2, len2, sizeof(char*),cmp_str_size);
         ^~~~~~~
In file included from /in/isSibling.c:2:0:
/usr/include/stdlib.h:827:13: note: expected 'void *' but argument is of type 'const char *'
 extern void qsort (void *__base, size_t __nmemb, size_t __size,
             ^~~~~
/in/isSibling.c:20:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^