Index: src/SynTree/Expression.cc
===================================================================
--- src/SynTree/Expression.cc	(revision f0ecf9bfb3ccc333894542767cb1c491f7e79993)
+++ src/SynTree/Expression.cc	(revision 8dceeb78ad2ff73a75b2a0589e7539e4da01800f)
@@ -324,7 +324,7 @@
 			return makeSub( refType->get_base() );
 		} else if ( StructInstType * aggInst = dynamic_cast< StructInstType * >( t ) ) {
-			return TypeSubstitution( aggInst->get_baseParameters()->begin(), aggInst->get_baseParameters()->end(), aggInst->get_parameters().begin() );
+			return TypeSubstitution( aggInst->get_baseParameters()->begin(), aggInst->get_baseParameters()->end(), aggInst->parameters.begin() );
 		} else if ( UnionInstType * aggInst = dynamic_cast< UnionInstType * >( t ) ) {
-			return TypeSubstitution( aggInst->get_baseParameters()->begin(), aggInst->get_baseParameters()->end(), aggInst->get_parameters().begin() );
+			return TypeSubstitution( aggInst->get_baseParameters()->begin(), aggInst->get_baseParameters()->end(), aggInst->parameters.begin() );
 		} else {
 			assertf( false, "makeSub expects struct or union type for aggregate, but got: %s", toString( t ).c_str() );