$OpenBSD: patch-gr-blocks_lib_socket_pdu_impl_cc,v 1.1 2021/03/18 19:51:44 rsadowski Exp $

Build with newer Boost. From Fedora.

Index: gr-blocks/lib/socket_pdu_impl.cc
--- gr-blocks/lib/socket_pdu_impl.cc.orig
+++ gr-blocks/lib/socket_pdu_impl.cc
@@ -32,6 +32,8 @@
 namespace gr {
 namespace blocks {
 
+using namespace boost::placeholders;
+
 socket_pdu::sptr socket_pdu::make(std::string type,
                                   std::string addr,
                                   std::string port,
