[Mingw-users] Undefined reference to 'getaddrinfo'

[James S. <jam...@op...>]

Hi All,

I've googled for this for a while now and I'm not sure what to do next.

I have a small c program that calls getaddrinfo and freeaddrinfo.

I have the header file included for ws2tcpip.h.

When I compile with
gcc -Wall -o prog main.c -lws2_32

I get warnings about implicit declarations of the 2 functions and
undefined references to the 2 functions from the linker.

In the ws2tcpip.h I see
#if (_WIN32_WINNT >= 0x0501)

---declaration of getaddrinfo

#else
/* FIXME ...

When I print the value of _WIN32_WINNT I get 0x400 so obviously the
function isn't declared.  That explains the implicit declarations
warning.  But what about the undefined references?  The functions are in
the library ws2_32.a.

What do I need to do to resolve this?  Is it a MinGW version or a
Windows version that needs updating?  Or something completely different?

I've attached a smaller test case that behaves similarly.

Regards,
James.

/*
gcc -Wall -o test test.c -lws2_32
test.c: In function `main':
test.c:27: warning: implicit declaration of function `getaddrinfo'
C:/DOCUME~1/James/LOCALS~1/Temp/ccw5baaa.o(.text+0xeb):test.c: undefined
reference to `getaddrinfo'
collect2: ld returned 1 exit status
 */  

#include <windows.h>
#include <stdio.h>
#include <winsock2.h>
#include <ws2tcpip.h>

#define DEF_PORT "27015"

int main(int argc, char **argv) {

        int rv;
        WSADATA wsaData;
        struct addrinfo *result = NULL, hints;

        rv = WSAStartup((short)0x0202, &wsaData);
        
        if (rv != 0) {
                printf("WSAStartup failed: %d\n", rv);
                return 1;
        }
        
        ZeroMemory(&hints, sizeof(hints));
        hints.ai_family = AF_INET;
        hints.ai_socktype = SOCK_DGRAM;
        hints.ai_protocol = IPPROTO_UDP;
        hints.ai_flags = AI_PASSIVE;

        rv = getaddrinfo(NULL, DEF_PORT, &hints, &result);
        if (rv != 0) {
                printf("getaddrinfo failed: %d\n", rv);
                WSACleanup();
                return 1;
        }

        WSACleanup();

        return 0;
}