2 files changed, 11 insertions, 1 deletions
diff --git a/gnuradio-runtime/include/gnuradio/basic_block.h b/gnuradio-runtime/include/gnuradio/basic_block.h
index 28552a483d..b413274ded 100644
--- a/gnuradio-runtime/include/gnuradio/basic_block.h
+++ b/gnuradio-runtime/include/gnuradio/basic_block.h
@@ -275,6 +275,10 @@ namespace gr {
       }
       return false;
     }
+    
+    const msg_queue_map_t& get_msg_map(void) const {
+      return msg_queue;
+    }
 
 #ifdef GR_CTRLPORT
     /*!
diff --git a/gnuradio-runtime/lib/flowgraph.cc b/gnuradio-runtime/lib/flowgraph.cc
index 3d8dfea65a..abe51f741d 100644
--- a/gnuradio-runtime/lib/flowgraph.cc
+++ b/gnuradio-runtime/lib/flowgraph.cc
@@ -155,8 +155,14 @@ namespace gr {
     if(FLOWGRAPH_DEBUG)
       std::cout << "check_valid_port( " << e.block() << ", " << e.port() << ")\n";
 
-    if(!e.block()->has_msg_port(e.port()))
+    if(!e.block()->has_msg_port(e.port())) {
+      const gr::basic_block::msg_queue_map_t& msg_map = e.block()->get_msg_map();
+      std::cout << "Could not find port: " << e.port() << " in:" << std::endl;
+      for (gr::basic_block::msg_queue_map_t::const_iterator it = msg_map.begin(); it != msg_map.end(); ++it)
+        std::cout << it->first << std::endl;
+      std::cout << std::endl;
       throw std::invalid_argument("invalid msg port in connect() or disconnect()");
+    }
   }
 
   void