diff --git a/src/Expr.cc b/src/Expr.cc
index fb2583fc6c..1ee6bd16ba 100644
--- a/src/Expr.cc
+++ b/src/Expr.cc
@@ -5195,7 +5195,7 @@ int check_and_promote_expr(Expr*& e, BroType* t)
 	return 1;
 	}
 
-int check_and_promote_exprs(ListExpr*& elements, TypeList* types)
+int check_and_promote_exprs(ListExpr*const elements, TypeList* types)
 	{
 	expr_list& el = elements->Exprs();
 	const type_list* tl = types->Types();
@@ -5225,7 +5225,7 @@ int check_and_promote_exprs(ListExpr*& elements, TypeList* types)
 	return 1;
 	}
 
-int check_and_promote_args(ListExpr*& args, RecordType* types)
+int check_and_promote_args(ListExpr*const args, RecordType* types)
 	{
 	expr_list& el = args->Exprs();
 	int ntypes = types->NumFields();
@@ -5269,7 +5269,7 @@ int check_and_promote_args(ListExpr*& args, RecordType* types)
 	return rval;
 	}
 
-int check_and_promote_exprs_to_type(ListExpr*& elements, BroType* type)
+int check_and_promote_exprs_to_type(ListExpr*const elements, BroType* type)
 	{
 	expr_list& el = elements->Exprs();
 
diff --git a/src/Expr.h b/src/Expr.h
index 701e826b19..1dce2d8370 100644
--- a/src/Expr.h
+++ b/src/Expr.h
@@ -1085,9 +1085,9 @@ Expr* get_assign_expr(Expr* op1, Expr* op2, int is_init);
 //
 // Note, the type is not "const" because it can be ref'd.
 extern int check_and_promote_expr(Expr*& e, BroType* t);
-extern int check_and_promote_exprs(ListExpr*& elements, TypeList* types);
-extern int check_and_promote_args(ListExpr*& args, RecordType* types);
-extern int check_and_promote_exprs_to_type(ListExpr*& elements, BroType* type);
+extern int check_and_promote_exprs(ListExpr* elements, TypeList* types);
+extern int check_and_promote_args(ListExpr* args, RecordType* types);
+extern int check_and_promote_exprs_to_type(ListExpr* elements, BroType* type);
 
 // Returns a ListExpr simplified down to a list a values, or a nil
 // pointer if they couldn't all be reduced.