diff --git a/vhdlpp/package.cc b/vhdlpp/package.cc
index e1a6c7de3..9c0025f47 100644
--- a/vhdlpp/package.cc
+++ b/vhdlpp/package.cc
@@ -75,6 +75,10 @@ void Package::write_to_stream(ostream&fd) const
 		  continue;
 	    if (cur->first == "std_logic_vector")
 		  continue;
+	    if (cur->first == "signed")
+		  continue;
+	    if (cur->first == "unsigned")
+		  continue;
 
 	    fd << "type " << cur->first << " is ";
 	    cur->second->write_type_to_stream(fd);