Milter-greylist

> > > Could you write a configure test that check that macro? 
> The work is
> > > easy, as we already have similar tests (for instance about
> > > -D__EXTENSIONS__)
> 
> [That's tricky]
> 
> What about tryig to use an IPv6 related structure with and 
> without OSF_SOURCE?
> If the result is (fail, suceed), that means we need to add 
> OSF_SOURCE to CFLAGS
> 
> That does not work?

Here it is:

$ cat tst.c
#include <sys/socket.h>
#include <netinet/in.h>

main()
  {
#ifdef AF_INET6
  struct in6_addr s;
#endif
  }
$ cc -D_XOPEN_SOURCE=500 -D_BSD_SOURCE -D_OSF_SOURCE -o tst tst.c
$ cc -D_XOPEN_SOURCE=500 -D_BSD_SOURCE -o tst tst.c
cc: Error: tst.c, line 7: In this declaration, "s" has no linkage and is of
an i
ncomplete type. (incompnolink)
  struct in6_addr s;
------------------^
$