Compilare: user.c: In function ‘main’: user.c:54:5: warning: passing argument 4 of ‘qsort’ from incompatible pointer type [enabled by default] qsort(v,n,sizeof(v[0]),compare); ^ In file included from user.c:2:0: /usr/include/stdlib.h:756:13: note: expected ‘__compar_fn_t’ but argument is of type ‘int (*)(struct cord *, struct cord *)’ extern void qsort (void *__base, size_t __nmemb, size_t __size, ^