simplify the ipv6 check

Author: vuvova

mysql-test/suite.pm

@@ -56,15 +56,10 @@ sub skip_combinations {
   sub ipv6_ok() {
     use Socket;
     return 0 unless socket my $sock, PF_INET6, SOCK_STREAM, getprotobyname('tcp');
-    my $ipv6_works = false;
+    $!="";
     # eval{}, if there's no Socket::sockaddr_in6 at all, old Perl installation <5.14
-    eval {
-      my $addr = sockaddr_in6($baseport, Socket::IN6ADDR_LOOPBACK) or return 0;
-      die 'bind failed' unless bind $sock, $addr;
-      close $sock;
-      $ipv6_works = true;
-    };
-    return $@ eq "" && $ipv6_works;
+    eval { bind $sock, sockaddr_in6($::baseport, Socket::IN6ADDR_LOOPBACK) };
+    return $@ eq "" && $! eq ""
   }
   $skip{'include/check_ipv6.inc'} = 'No IPv6' unless ipv6_ok();