Index: src/SynTree/Expression.cc
===================================================================
--- src/SynTree/Expression.cc	(revision 141b7868c72c7947affae41e61e4bfcd7f9c6652)
+++ src/SynTree/Expression.cc	(revision d7bcbf5a448434f2bcfc247bc16c0f111feaca9a)
@@ -422,5 +422,8 @@
 }
 
-NameExpr::NameExpr( std::string _name, Expression *_aname ) : Expression( _aname ), name(_name) {}
+NameExpr::NameExpr( std::string _name, Expression *_aname ) : Expression( _aname ), name(_name) {
+	assertf(_name != "0", "Zero is not a valid name\n");
+	assertf(_name != "1", "One is not a valid name\n");
+}
 
 NameExpr::NameExpr( const NameExpr &other ) : Expression( other ), name( other.name ) {
Index: src/SynTree/Type.h
===================================================================
--- src/SynTree/Type.h	(revision 141b7868c72c7947affae41e61e4bfcd7f9c6652)
+++ src/SynTree/Type.h	(revision d7bcbf5a448434f2bcfc247bc16c0f111feaca9a)
@@ -81,4 +81,6 @@
 	ForallList forall;
 };
+
+extern Type::Qualifiers emptyQualifiers;				// no qualifiers on constants
 
 class VoidType : public Type {