diff --git a/src/library/tactic/smt/ematch.h b/src/library/tactic/smt/ematch.h
index b0bdcfd27a..858d3a3d9e 100644
--- a/src/library/tactic/smt/ematch.h
+++ b/src/library/tactic/smt/ematch.h
@@ -19,10 +19,10 @@ struct ematch_config {
     unsigned  m_max_generation{10};
 };
 
-struct ematch_fn;
+class ematch_fn;
 
 class ematch_state {
-    friend struct ematch_fn;
+    friend class ematch_fn;
     app_map               m_app_map;
     rb_expr_set           m_instances;
     unsigned              m_num_instances{0};