想编译一下ht代码/src/下的单个程序，方便用gdb跟踪来看懂此程序，但却总编译不成功，难道src下的程序，不能单独编译？
[bbs@xztu debug]$ gcc -g -o delete delete.c
delete.c:259: dereferencing pointer to incomplete type
delete.c:265: dereferencing pointer to incomplete type
delete.c:266: dereferencing pointer to incomplete type
delete.c: In function `kick_user':
delete.c:279: storage size of `uin' isn't known
delete.c:283: invalid use of undefined type `struct user_info'
delete.c:283: `LUSERS' undeclared (first use in this function)
delete.c:283: invalid use of undefined type `struct user_info'
delete.c:284: `OFFLINE' undeclared (first use in this function)
delete.c:284: invalid use of undefined type `struct user_info'
delete.c:284: `FRIEND' undeclared (first use in this function)
delete.c:285: `ADMIN' undeclared (first use in this function)
delete.c:304: `YEA' undeclared (first use in this function)
delete.c:312: `t_cmpuids' undeclared (first use in this function)
delete.c:314: dereferencing pointer to incomplete type
delete.c:322: invalid use of undefined type `struct user_info'
delete.c:322: invalid use of undefined type `struct user_info'
delete.c:323: invalid use of undefined type `struct user_info'
delete.c:331: `SIGHUP' undeclared (first use in this function)
delete.c:337: dereferencing pointer to incomplete type
delete.c:339: invalid use of undefined type `struct user_info'
delete.c:339: invalid use of undefined type `struct user_info'
delete.c:340: invalid use of undefined type `struct user_info'
--
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