diff --git a/src/emqx_gc.erl b/src/emqx_gc.erl
index 7d47b7071..5f939bfe5 100644
--- a/src/emqx_gc.erl
+++ b/src/emqx_gc.erl
@@ -34,7 +34,7 @@
         , reset/1
         ]).
 
--export_type([gc_state/0]).
+-export_type([opts/0, gc_state/0]).
 
 -type(opts() :: #{count => integer(),
                   bytes => integer()}).
diff --git a/src/emqx_oom.erl b/src/emqx_oom.erl
index 8d3344402..efc0a4c69 100644
--- a/src/emqx_oom.erl
+++ b/src/emqx_oom.erl
@@ -28,7 +28,7 @@
         , info/1
         ]).
 
--export_type([oom_policy/0]).
+-export_type([opts/0, oom_policy/0]).
 
 -type(opts() :: #{message_queue_len => non_neg_integer(),
                   max_heap_size => non_neg_integer()