diff --git a/backends/aiger2/aiger.cc b/backends/aiger2/aiger.cc
index bc22dac94..0c787f11d 100644
--- a/backends/aiger2/aiger.cc
+++ b/backends/aiger2/aiger.cc
@@ -413,7 +413,7 @@ struct Index {
 		}
 	};
 
-	int visit(HierCursor &cursor, SigBit bit)
+	Lit visit(HierCursor &cursor, SigBit bit)
 	{
 		if (!bit.wire) {
 			if (bit == State::S1)