The libgnomevfs/gnome-vfs-address.c file uses the IN6_ARE_ADDR_EQUAL macro in a way that only works in Linux, thus breaking the build in, e.g., NetBSD or Solaris.  The problem is that the call messes with in6_addr internals by accessing their s6_addr field, which in several platforms is "mapped" to an array, not a structure.

Consider the following test program, which mimics gnome-vfs-address.c's way of calling the offending macro:

#include <stdio.h>
#include <netinet/in.h>

int
main(void)
{
        const struct sockaddr_in6 *a = NULL;
        const struct sockaddr_in6 *b = NULL;

        return IN6_ARE_ADDR_EQUAL(a->sin6_addr.s6_addr, b->sin6_addr.s6_addr);
}


Building this test case in NetBSD gives:

test.c: In function `main':
test.c:10: error: request for member `__u6_addr' in something not a structure or union
test.c:10: error: request for member `__u6_addr' in something not a structure or union

Building this test case in Solaris gives:

test.c: In function `main':
test.c:10: error: request for member `_S6_un' in something not a structure or union
test.c:10: error: request for member `_S6_un' in something not a structure or union
test.c:10: error: request for member `_S6_un' in something not a structure or union
test.c:10: error: request for member `_S6_un' in something not a structure or union
test.c:10: error: request for member `_S6_un' in something not a structure or union
test.c:10: error: request for member `_S6_un' in something not a structure or union
test.c:10: error: request for member `_S6_un' in something not a structure or union
test.c:10: error: request for member `_S6_un' in something not a structure or union

Building it in Linux works, though.

In order to fix this, the code should pass the in6_addr structure to the macro, not one of its fields, and let the macro take appropriate action.  I.e., the code above could say &a->sin6_addr instead of a->sin6_addr.s6_addr.

After applying the attached patch, the affected file builds in NetBSD, Solaris and, of course, Linux.