diff --git a/imperative/python/src/graph_rt.h b/imperative/python/src/graph_rt.h
index 85d84bd4454cd2676854637dfffbdd52fa44c178..b9116211cb0cc70fa6d8604247712ffefbb4dbf6 100644
--- a/imperative/python/src/graph_rt.h
+++ b/imperative/python/src/graph_rt.h
@@ -44,15 +44,8 @@ class Rendezvous {
 public:
     Rendezvous() = default;
     Rendezvous(const Rendezvous& rhs) = delete;
-    Rendezvous(Rendezvous&& rhs) = default;
+    Rendezvous(Rendezvous&& rhs) = delete;
     Rendezvous& operator=(const Rendezvous& rhs) = delete;
-    Rendezvous& operator=(Rendezvous&& rhs) {
-        MGB_LOCK_GUARD(m_lock);
-        m_drop_next = rhs.m_drop_next;
-        m_read_ahead = rhs.m_read_ahead;
-        m_promise = std::move(rhs.m_promise);
-        return *this;
-    }
 
     R get() {
         std::future<R> f;
diff --git a/imperative/src/impl/opr_utility.cpp b/imperative/src/impl/opr_utility.cpp
index d5f9a1c001318ece42efb6377846fd155895a6c9..5a983f0d1d8589a185ced5861335a9987a79a1ca 100644
--- a/imperative/src/impl/opr_utility.cpp
+++ b/imperative/src/impl/opr_utility.cpp
@@ -123,6 +123,7 @@ OutputCallback::OutputCallback(Param param, const VarNodeArray& inputs,
             ->add_flag(VarNode::Flag::ALLOW_EMPTY_SHAPE)
             .add_flag(VarNode::Flag::NO_SYS_MEM_ALLOC)
             .dtype(DType::from_enum(DTypeEnum::Byte));
+    add_equivalence_component<ScalarHash<void*>>(this);
 }
 
 SymbolVar OutputCallback::make(Param param, const SymbolVarArray& inputs) {