未定义引用`_GetAdaptersAddresses @ 20' - 但我包括-liphlpapi

Question

我正在使用gccunder cygwin编写一些代码,这些代码在我的代码中调用GetAdaptersAddresses,iphlpapi.h我已经设置了_WIN32_WINNT上面所需的代码,0x0501并且在我添加的链接器行上-liphlpapi但链接器仍然失败并显示以下消息:

gcc -liphlpapi build/obj/*.o -Wall -Wextra -o build/bin/asdf.exe src/asdf.cpp
/tmp/ccdjLPVY.o:asdf.cpp:(.text+0x153): undefined reference to `_GetAdaptersAddresses@20'
collect2: ld returned 1 exit status

一些片段来自asdf.cpp:

#if _WIN32_WINNT < 0x0501
  #warning _WIN32_WINNT was set lower than 0x0501, fixing
  #undef _WIN32_WINNT
  #define _WIN32_WINNT 0x0501
#endif
#include <winsock2.h>
#include <iphlpapi.h>

我知道他们在那里蠢蠢欲动:

strings /usr/i686-pc-mingw32/sys-root/mingw/lib/libiphlpapi.a  | sort | uniq | grep GetAdapters
__imp__GetAdaptersAddresses@20
__imp__GetAdaptersInfo@8
_GetAdaptersAddresses@20
_GetAdaptersInfo@8
GetAdaptersAddresses
GetAdaptersInfo

$strings /usr/lib/w32api/libiphlpapi.a  | sort | uniq | grep GetAdapters
__imp__GetAdaptersAddresses@20
__imp__GetAdaptersInfo@8
_GetAdaptersAddresses@20
_GetAdaptersInfo@8
GetAdaptersAddresses
GetAdaptersInfo

有人看到我错过了什么吗？

编辑:答案

# Change the order, put the linker options last:
# Before:
gcc -liphlpapi build/obj/*.o -Wall -Wextra -o build/bin/asdf.exe src/asdf.cpp
# After:
gcc            build/obj/*.o -Wall -Wextra -o build/bin/asdf.exe src/asdf.cpp -liphlpapi

Answer 1

正如这个问题所解释的那样,gcc参数的顺序很重要.您需要将库包含移到依赖它的对象之后.

所以 gcc build/obj/*.o -liphlpapi ...