KLEE警告未定义函数

Question

我将Wireshark编译成LLVM，然后针对一些库进行链接，这些库也被编译成LLVM。

我所链接的库是libwsutil、libz和libpcap。然而，KLEE仍然对libpcap的未定义函数发出警告。

我使用以下标志编译了libpcap：

CC="llvm-gcc" CFLAGS="-flto -c" AR="llvm-ar" LD="llvm-ld"

这些标志也适用于其他库。

可能是什么原因？

KLEE: WARNING ONCE: function "capture_loop_dispatch" has inline asm
KLEE: WARNING ONCE: function "__user_main" has inline asm
KLEE: WARNING: undefined reference to function: __ctype_b_loc
KLEE: WARNING: undefined reference to function: __xstat64
KLEE: WARNING: undefined reference to function: bpf_image
KLEE: WARNING: undefined reference to function: cap_free
KLEE: WARNING: undefined reference to function: cap_init
KLEE: WARNING: undefined reference to function: cap_set_flag
KLEE: WARNING: undefined reference to function: cap_set_proc
...
...
KLEE: WARNING: undefined reference to function: lseek64
KLEE: WARNING: undefined reference to function: pcap_activate
KLEE: WARNING: undefined reference to function: pcap_breakloop
KLEE: WARNING: undefined reference to function: pcap_can_set_rfmon
KLEE: WARNING: undefined reference to function: pcap_close
KLEE: WARNING: undefined reference to function: pcap_compile
KLEE: WARNING: undefined reference to function: pcap_create
KLEE: WARNING: undefined reference to function: pcap_datalink
KLEE: WARNING: undefined reference to function: pcap_datalink_name_to_val
KLEE: WARNING: undefined reference to function: pcap_datalink_val_to_description
KLEE: WARNING: undefined reference to function: pcap_datalink_val_to_name
KLEE: WARNING: undefined reference to function: pcap_dispatch
KLEE: WARNING: undefined reference to function: pcap_findalldevs
KLEE: WARNING: undefined reference to function: pcap_free_datalinks
KLEE: WARNING: undefined reference to function: pcap_freealldevs
KLEE: WARNING: undefined reference to function: pcap_freecode
KLEE: WARNING: undefined reference to function: pcap_get_selectable_fd
KLEE: WARNING: undefined reference to function: pcap_geterr
KLEE: WARNING: undefined reference to function: pcap_lib_version
KLEE: WARNING: undefined reference to function: pcap_list_datalinks
KLEE: WARNING: undefined reference to function: pcap_lookupnet
KLEE: WARNING: undefined reference to function: pcap_open_live
KLEE: WARNING: undefined reference to function: pcap_set_buffer_size
KLEE: WARNING: undefined reference to function: pcap_set_datalink
KLEE: WARNING: undefined reference to function: pcap_set_promisc
KLEE: WARNING: undefined reference to function: pcap_set_rfmon
KLEE: WARNING: undefined reference to function: pcap_set_snaplen
KLEE: WARNING: undefined reference to function: pcap_set_timeout
KLEE: WARNING: undefined reference to function: pcap_setfilter
KLEE: WARNING: undefined reference to function: pcap_snapshot
KLEE: WARNING: undefined reference to function: pcap_stats
KLEE: WARNING: undefined reference to function: pcap_statustostr
KLEE: WARNING: undefined reference to function: prctl

Answer 1

在快速入门阅读KLEE的“入门”

默认情况下，KLEE处理封闭程序(不使用任何外部代码(如C库函数)的程序)。但是，如果您想使用KLEE运行真正的程序，您将需要启用KLEE运行时，它构建在uClibc C库之上。

因此，KLEE不能默认使用C库函数，如果您在选项libc=uclibc中使用KLEE，则KLEE将将外部函数链接到您的IR代码中，并执行IR代码