diff --git a/lib/shared_memory.c b/lib/shared_memory.c
index eec06d4e..d1d6f42f 100644
--- a/lib/shared_memory.c
+++ b/lib/shared_memory.c
@@ -16,6 +16,12 @@ _dtor(struct import_object *imo)
         }
 }
 
+/*
+ * create shared memories to satisfy all shared memory imports
+ * in the module.
+ *
+ * used for wasi-threads.
+ */
 int
 create_satisfying_shared_memories(struct module *m,
                                   struct import_object **imop)