diff --git a/samples/monster_generated.h b/samples/monster_generated.h
index 74cb96253..a2a8308bd 100644
--- a/samples/monster_generated.h
+++ b/samples/monster_generated.h
@@ -564,7 +564,7 @@ inline void Monster::UnPackTo(MonsterT *_o, const flatbuffers::resolver_function
   { auto _e = name(); if (_e) _o->name = _e->str(); }
   { auto _e = inventory(); if (_e) { _o->inventory.resize(_e->size()); std::copy(_e->begin(), _e->end(), _o->inventory.begin()); } }
   { auto _e = color(); _o->color = _e; }
-  { auto _e = weapons(); if (_e) { _o->weapons.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->weapons[_i] = flatbuffers::unique_ptr<MyGame::Sample::WeaponT>(_e->Get(_i)->UnPack(_resolver)); } } }
+  { auto _e = weapons(); if (_e) { _o->weapons.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { if(_o->weapons[_i]) { _e->Get(_i)->UnPackTo(_o->weapons[_i].get(), _resolver); } else { _o->weapons[_i] = flatbuffers::unique_ptr<MyGame::Sample::WeaponT>(_e->Get(_i)->UnPack(_resolver)); }; } } }
   { auto _e = equipped_type(); _o->equipped.type = _e; }
   { auto _e = equipped(); if (_e) _o->equipped.value = MyGame::Sample::EquipmentUnion::UnPack(_e, equipped_type(), _resolver); }
   { auto _e = path(); if (_e) { _o->path.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->path[_i] = *_e->Get(_i); } } }
diff --git a/src/idl_gen_cpp.cpp b/src/idl_gen_cpp.cpp
index 019845db4..455637127 100644
--- a/src/idl_gen_cpp.cpp
+++ b/src/idl_gen_cpp.cpp
@@ -2767,9 +2767,19 @@ class CppGenerator : public BaseGenerator {
               code += "/* else do nothing */";
             }
           } else {
+            const bool is_pointer =
+                field.value.type.VectorType().base_type == BASE_TYPE_STRUCT &&
+                !IsStruct(field.value.type.VectorType());
+            if (is_pointer) {
+              code += "if(_o->" + name + "[_i]" + ") { ";
+              code += indexing + "->UnPackTo(_o->" + name +
+                      "[_i].get(), _resolver);";
+              code += " } else { ";
+            }
             code += "_o->" + name + "[_i]" + access + " = ";
             code += GenUnpackVal(field.value.type.VectorType(), indexing, true,
                                  field);
+            if (is_pointer) { code += "; }"; }
           }
           code += "; } }";
         }
@@ -2816,8 +2826,17 @@ class CppGenerator : public BaseGenerator {
         } else {
           // Generate code for assigning the value, of the form:
           //  _o->field = value;
+          const bool is_pointer =
+              field.value.type.base_type == BASE_TYPE_STRUCT &&
+              !IsStruct(field.value.type);
+          if (is_pointer) {
+            code += "{ if(_o->" + Name(field) + ") { ";
+            code += "_e->UnPackTo(_o->" + Name(field) + ".get(), _resolver);";
+            code += " } else { ";
+          }
           code += "_o->" + Name(field) + " = ";
           code += GenUnpackVal(field.value.type, "_e", false, field) + ";";
+          if (is_pointer) { code += " } }"; }
         }
         break;
       }
diff --git a/tests/cpp17/generated_cpp17/monster_test_generated.h b/tests/cpp17/generated_cpp17/monster_test_generated.h
index 06477eab3..c95be273f 100644
--- a/tests/cpp17/generated_cpp17/monster_test_generated.h
+++ b/tests/cpp17/generated_cpp17/monster_test_generated.h
@@ -2686,10 +2686,10 @@ inline void Monster::UnPackTo(MonsterT *_o, const flatbuffers::resolver_function
   { auto _e = test(); if (_e) _o->test.value = MyGame::Example::AnyUnion::UnPack(_e, test_type(), _resolver); }
   { auto _e = test4(); if (_e) { _o->test4.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->test4[_i] = *_e->Get(_i); } } }
   { auto _e = testarrayofstring(); if (_e) { _o->testarrayofstring.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->testarrayofstring[_i] = _e->Get(_i)->str(); } } }
-  { auto _e = testarrayoftables(); if (_e) { _o->testarrayoftables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->testarrayoftables[_i] = std::unique_ptr<MyGame::Example::MonsterT>(_e->Get(_i)->UnPack(_resolver)); } } }
-  { auto _e = enemy(); if (_e) _o->enemy = std::unique_ptr<MyGame::Example::MonsterT>(_e->UnPack(_resolver)); }
+  { auto _e = testarrayoftables(); if (_e) { _o->testarrayoftables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { if(_o->testarrayoftables[_i]) { _e->Get(_i)->UnPackTo(_o->testarrayoftables[_i].get(), _resolver); } else { _o->testarrayoftables[_i] = std::unique_ptr<MyGame::Example::MonsterT>(_e->Get(_i)->UnPack(_resolver)); }; } } }
+  { auto _e = enemy(); if (_e) { if(_o->enemy) { _e->UnPackTo(_o->enemy.get(), _resolver); } else { _o->enemy = std::unique_ptr<MyGame::Example::MonsterT>(_e->UnPack(_resolver)); } } }
   { auto _e = testnestedflatbuffer(); if (_e) { _o->testnestedflatbuffer.resize(_e->size()); std::copy(_e->begin(), _e->end(), _o->testnestedflatbuffer.begin()); } }
-  { auto _e = testempty(); if (_e) _o->testempty = std::unique_ptr<MyGame::Example::StatT>(_e->UnPack(_resolver)); }
+  { auto _e = testempty(); if (_e) { if(_o->testempty) { _e->UnPackTo(_o->testempty.get(), _resolver); } else { _o->testempty = std::unique_ptr<MyGame::Example::StatT>(_e->UnPack(_resolver)); } } }
   { auto _e = testbool(); _o->testbool = _e; }
   { auto _e = testhashs32_fnv1(); _o->testhashs32_fnv1 = _e; }
   { auto _e = testhashu32_fnv1(); _o->testhashu32_fnv1 = _e; }
@@ -2710,13 +2710,13 @@ if (_resolver) (*_resolver)(reinterpret_cast<void **>(&_o->testhashu32_fnv1a), s
   { auto _e = test5(); if (_e) { _o->test5.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->test5[_i] = *_e->Get(_i); } } }
   { auto _e = vector_of_longs(); if (_e) { _o->vector_of_longs.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->vector_of_longs[_i] = _e->Get(_i); } } }
   { auto _e = vector_of_doubles(); if (_e) { _o->vector_of_doubles.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->vector_of_doubles[_i] = _e->Get(_i); } } }
-  { auto _e = parent_namespace_test(); if (_e) _o->parent_namespace_test = std::unique_ptr<MyGame::InParentNamespaceT>(_e->UnPack(_resolver)); }
-  { auto _e = vector_of_referrables(); if (_e) { _o->vector_of_referrables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->vector_of_referrables[_i] = std::unique_ptr<MyGame::Example::ReferrableT>(_e->Get(_i)->UnPack(_resolver)); } } }
+  { auto _e = parent_namespace_test(); if (_e) { if(_o->parent_namespace_test) { _e->UnPackTo(_o->parent_namespace_test.get(), _resolver); } else { _o->parent_namespace_test = std::unique_ptr<MyGame::InParentNamespaceT>(_e->UnPack(_resolver)); } } }
+  { auto _e = vector_of_referrables(); if (_e) { _o->vector_of_referrables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { if(_o->vector_of_referrables[_i]) { _e->Get(_i)->UnPackTo(_o->vector_of_referrables[_i].get(), _resolver); } else { _o->vector_of_referrables[_i] = std::unique_ptr<MyGame::Example::ReferrableT>(_e->Get(_i)->UnPack(_resolver)); }; } } }
   { auto _e = single_weak_reference(); //scalar resolver, naked 
 if (_resolver) (*_resolver)(reinterpret_cast<void **>(&_o->single_weak_reference), static_cast<flatbuffers::hash_value_t>(_e)); else _o->single_weak_reference = nullptr; }
   { auto _e = vector_of_weak_references(); if (_e) { _o->vector_of_weak_references.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { //vector resolver, naked
 if (_resolver) (*_resolver)(reinterpret_cast<void **>(&_o->vector_of_weak_references[_i]), static_cast<flatbuffers::hash_value_t>(_e->Get(_i))); else _o->vector_of_weak_references[_i] = nullptr; } } }
-  { auto _e = vector_of_strong_referrables(); if (_e) { _o->vector_of_strong_referrables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->vector_of_strong_referrables[_i] = std::unique_ptr<MyGame::Example::ReferrableT>(_e->Get(_i)->UnPack(_resolver)); } } }
+  { auto _e = vector_of_strong_referrables(); if (_e) { _o->vector_of_strong_referrables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { if(_o->vector_of_strong_referrables[_i]) { _e->Get(_i)->UnPackTo(_o->vector_of_strong_referrables[_i].get(), _resolver); } else { _o->vector_of_strong_referrables[_i] = std::unique_ptr<MyGame::Example::ReferrableT>(_e->Get(_i)->UnPack(_resolver)); }; } } }
   { auto _e = co_owning_reference(); //scalar resolver, naked 
 if (_resolver) (*_resolver)(reinterpret_cast<void **>(&_o->co_owning_reference), static_cast<flatbuffers::hash_value_t>(_e)); else _o->co_owning_reference = nullptr; }
   { auto _e = vector_of_co_owning_references(); if (_e) { _o->vector_of_co_owning_references.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { //vector resolver, default_ptr_type
@@ -2732,7 +2732,7 @@ if (_resolver) (*_resolver)(reinterpret_cast<void **>(&_o->vector_of_non_owning_
   { auto _e = vector_of_enums(); if (_e) { _o->vector_of_enums.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->vector_of_enums[_i] = static_cast<MyGame::Example::Color>(_e->Get(_i)); } } }
   { auto _e = signed_enum(); _o->signed_enum = _e; }
   { auto _e = testrequirednestedflatbuffer(); if (_e) { _o->testrequirednestedflatbuffer.resize(_e->size()); std::copy(_e->begin(), _e->end(), _o->testrequirednestedflatbuffer.begin()); } }
-  { auto _e = scalar_key_sorted_tables(); if (_e) { _o->scalar_key_sorted_tables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->scalar_key_sorted_tables[_i] = std::unique_ptr<MyGame::Example::StatT>(_e->Get(_i)->UnPack(_resolver)); } } }
+  { auto _e = scalar_key_sorted_tables(); if (_e) { _o->scalar_key_sorted_tables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { if(_o->scalar_key_sorted_tables[_i]) { _e->Get(_i)->UnPackTo(_o->scalar_key_sorted_tables[_i].get(), _resolver); } else { _o->scalar_key_sorted_tables[_i] = std::unique_ptr<MyGame::Example::StatT>(_e->Get(_i)->UnPack(_resolver)); }; } } }
 }
 
 inline flatbuffers::Offset<Monster> Monster::Pack(flatbuffers::FlatBufferBuilder &_fbb, const MonsterT* _o, const flatbuffers::rehasher_function_t *_rehasher) {
diff --git a/tests/monster_test_generated.h b/tests/monster_test_generated.h
index 1a887aabc..575bff25d 100644
--- a/tests/monster_test_generated.h
+++ b/tests/monster_test_generated.h
@@ -2635,10 +2635,10 @@ inline void Monster::UnPackTo(MonsterT *_o, const flatbuffers::resolver_function
   { auto _e = test(); if (_e) _o->test.value = MyGame::Example::AnyUnion::UnPack(_e, test_type(), _resolver); }
   { auto _e = test4(); if (_e) { _o->test4.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->test4[_i] = *_e->Get(_i); } } }
   { auto _e = testarrayofstring(); if (_e) { _o->testarrayofstring.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->testarrayofstring[_i] = _e->Get(_i)->str(); } } }
-  { auto _e = testarrayoftables(); if (_e) { _o->testarrayoftables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->testarrayoftables[_i] = flatbuffers::unique_ptr<MyGame::Example::MonsterT>(_e->Get(_i)->UnPack(_resolver)); } } }
-  { auto _e = enemy(); if (_e) _o->enemy = flatbuffers::unique_ptr<MyGame::Example::MonsterT>(_e->UnPack(_resolver)); }
+  { auto _e = testarrayoftables(); if (_e) { _o->testarrayoftables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { if(_o->testarrayoftables[_i]) { _e->Get(_i)->UnPackTo(_o->testarrayoftables[_i].get(), _resolver); } else { _o->testarrayoftables[_i] = flatbuffers::unique_ptr<MyGame::Example::MonsterT>(_e->Get(_i)->UnPack(_resolver)); }; } } }
+  { auto _e = enemy(); if (_e) { if(_o->enemy) { _e->UnPackTo(_o->enemy.get(), _resolver); } else { _o->enemy = flatbuffers::unique_ptr<MyGame::Example::MonsterT>(_e->UnPack(_resolver)); } } }
   { auto _e = testnestedflatbuffer(); if (_e) { _o->testnestedflatbuffer.resize(_e->size()); std::copy(_e->begin(), _e->end(), _o->testnestedflatbuffer.begin()); } }
-  { auto _e = testempty(); if (_e) _o->testempty = flatbuffers::unique_ptr<MyGame::Example::StatT>(_e->UnPack(_resolver)); }
+  { auto _e = testempty(); if (_e) { if(_o->testempty) { _e->UnPackTo(_o->testempty.get(), _resolver); } else { _o->testempty = flatbuffers::unique_ptr<MyGame::Example::StatT>(_e->UnPack(_resolver)); } } }
   { auto _e = testbool(); _o->testbool = _e; }
   { auto _e = testhashs32_fnv1(); _o->testhashs32_fnv1 = _e; }
   { auto _e = testhashu32_fnv1(); _o->testhashu32_fnv1 = _e; }
@@ -2659,13 +2659,13 @@ if (_resolver) (*_resolver)(reinterpret_cast<void **>(&_o->testhashu32_fnv1a), s
   { auto _e = test5(); if (_e) { _o->test5.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->test5[_i] = *_e->Get(_i); } } }
   { auto _e = vector_of_longs(); if (_e) { _o->vector_of_longs.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->vector_of_longs[_i] = _e->Get(_i); } } }
   { auto _e = vector_of_doubles(); if (_e) { _o->vector_of_doubles.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->vector_of_doubles[_i] = _e->Get(_i); } } }
-  { auto _e = parent_namespace_test(); if (_e) _o->parent_namespace_test = flatbuffers::unique_ptr<MyGame::InParentNamespaceT>(_e->UnPack(_resolver)); }
-  { auto _e = vector_of_referrables(); if (_e) { _o->vector_of_referrables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->vector_of_referrables[_i] = flatbuffers::unique_ptr<MyGame::Example::ReferrableT>(_e->Get(_i)->UnPack(_resolver)); } } }
+  { auto _e = parent_namespace_test(); if (_e) { if(_o->parent_namespace_test) { _e->UnPackTo(_o->parent_namespace_test.get(), _resolver); } else { _o->parent_namespace_test = flatbuffers::unique_ptr<MyGame::InParentNamespaceT>(_e->UnPack(_resolver)); } } }
+  { auto _e = vector_of_referrables(); if (_e) { _o->vector_of_referrables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { if(_o->vector_of_referrables[_i]) { _e->Get(_i)->UnPackTo(_o->vector_of_referrables[_i].get(), _resolver); } else { _o->vector_of_referrables[_i] = flatbuffers::unique_ptr<MyGame::Example::ReferrableT>(_e->Get(_i)->UnPack(_resolver)); }; } } }
   { auto _e = single_weak_reference(); //scalar resolver, naked 
 if (_resolver) (*_resolver)(reinterpret_cast<void **>(&_o->single_weak_reference), static_cast<flatbuffers::hash_value_t>(_e)); else _o->single_weak_reference = nullptr; }
   { auto _e = vector_of_weak_references(); if (_e) { _o->vector_of_weak_references.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { //vector resolver, naked
 if (_resolver) (*_resolver)(reinterpret_cast<void **>(&_o->vector_of_weak_references[_i]), static_cast<flatbuffers::hash_value_t>(_e->Get(_i))); else _o->vector_of_weak_references[_i] = nullptr; } } }
-  { auto _e = vector_of_strong_referrables(); if (_e) { _o->vector_of_strong_referrables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->vector_of_strong_referrables[_i] = flatbuffers::unique_ptr<MyGame::Example::ReferrableT>(_e->Get(_i)->UnPack(_resolver)); } } }
+  { auto _e = vector_of_strong_referrables(); if (_e) { _o->vector_of_strong_referrables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { if(_o->vector_of_strong_referrables[_i]) { _e->Get(_i)->UnPackTo(_o->vector_of_strong_referrables[_i].get(), _resolver); } else { _o->vector_of_strong_referrables[_i] = flatbuffers::unique_ptr<MyGame::Example::ReferrableT>(_e->Get(_i)->UnPack(_resolver)); }; } } }
   { auto _e = co_owning_reference(); //scalar resolver, naked 
 if (_resolver) (*_resolver)(reinterpret_cast<void **>(&_o->co_owning_reference), static_cast<flatbuffers::hash_value_t>(_e)); else _o->co_owning_reference = nullptr; }
   { auto _e = vector_of_co_owning_references(); if (_e) { _o->vector_of_co_owning_references.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { //vector resolver, default_ptr_type
@@ -2681,7 +2681,7 @@ if (_resolver) (*_resolver)(reinterpret_cast<void **>(&_o->vector_of_non_owning_
   { auto _e = vector_of_enums(); if (_e) { _o->vector_of_enums.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->vector_of_enums[_i] = static_cast<MyGame::Example::Color>(_e->Get(_i)); } } }
   { auto _e = signed_enum(); _o->signed_enum = _e; }
   { auto _e = testrequirednestedflatbuffer(); if (_e) { _o->testrequirednestedflatbuffer.resize(_e->size()); std::copy(_e->begin(), _e->end(), _o->testrequirednestedflatbuffer.begin()); } }
-  { auto _e = scalar_key_sorted_tables(); if (_e) { _o->scalar_key_sorted_tables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { _o->scalar_key_sorted_tables[_i] = flatbuffers::unique_ptr<MyGame::Example::StatT>(_e->Get(_i)->UnPack(_resolver)); } } }
+  { auto _e = scalar_key_sorted_tables(); if (_e) { _o->scalar_key_sorted_tables.resize(_e->size()); for (flatbuffers::uoffset_t _i = 0; _i < _e->size(); _i++) { if(_o->scalar_key_sorted_tables[_i]) { _e->Get(_i)->UnPackTo(_o->scalar_key_sorted_tables[_i].get(), _resolver); } else { _o->scalar_key_sorted_tables[_i] = flatbuffers::unique_ptr<MyGame::Example::StatT>(_e->Get(_i)->UnPack(_resolver)); }; } } }
 }
 
 inline flatbuffers::Offset<Monster> Monster::Pack(flatbuffers::FlatBufferBuilder &_fbb, const MonsterT* _o, const flatbuffers::rehasher_function_t *_rehasher) {
diff --git a/tests/namespace_test/namespace_test2_generated.h b/tests/namespace_test/namespace_test2_generated.h
index b53bc1517..8db01254b 100644
--- a/tests/namespace_test/namespace_test2_generated.h
+++ b/tests/namespace_test/namespace_test2_generated.h
@@ -359,7 +359,7 @@ inline TableInFirstNST *TableInFirstNS::UnPack(const flatbuffers::resolver_funct
 inline void TableInFirstNS::UnPackTo(TableInFirstNST *_o, const flatbuffers::resolver_function_t *_resolver) const {
   (void)_o;
   (void)_resolver;
-  { auto _e = foo_table(); if (_e) _o->foo_table = flatbuffers::unique_ptr<NamespaceA::NamespaceB::TableInNestedNST>(_e->UnPack(_resolver)); }
+  { auto _e = foo_table(); if (_e) { if(_o->foo_table) { _e->UnPackTo(_o->foo_table.get(), _resolver); } else { _o->foo_table = flatbuffers::unique_ptr<NamespaceA::NamespaceB::TableInNestedNST>(_e->UnPack(_resolver)); } } }
   { auto _e = foo_enum(); _o->foo_enum = _e; }
   { auto _e = foo_union_type(); _o->foo_union.type = _e; }
   { auto _e = foo_union(); if (_e) _o->foo_union.value = NamespaceA::NamespaceB::UnionInNestedNSUnion::UnPack(_e, foo_union_type(), _resolver); }
@@ -413,8 +413,8 @@ inline TableInCT *TableInC::UnPack(const flatbuffers::resolver_function_t *_reso
 inline void TableInC::UnPackTo(TableInCT *_o, const flatbuffers::resolver_function_t *_resolver) const {
   (void)_o;
   (void)_resolver;
-  { auto _e = refer_to_a1(); if (_e) _o->refer_to_a1 = flatbuffers::unique_ptr<NamespaceA::TableInFirstNST>(_e->UnPack(_resolver)); }
-  { auto _e = refer_to_a2(); if (_e) _o->refer_to_a2 = flatbuffers::unique_ptr<NamespaceA::SecondTableInAT>(_e->UnPack(_resolver)); }
+  { auto _e = refer_to_a1(); if (_e) { if(_o->refer_to_a1) { _e->UnPackTo(_o->refer_to_a1.get(), _resolver); } else { _o->refer_to_a1 = flatbuffers::unique_ptr<NamespaceA::TableInFirstNST>(_e->UnPack(_resolver)); } } }
+  { auto _e = refer_to_a2(); if (_e) { if(_o->refer_to_a2) { _e->UnPackTo(_o->refer_to_a2.get(), _resolver); } else { _o->refer_to_a2 = flatbuffers::unique_ptr<NamespaceA::SecondTableInAT>(_e->UnPack(_resolver)); } } }
 }
 
 inline flatbuffers::Offset<TableInC> TableInC::Pack(flatbuffers::FlatBufferBuilder &_fbb, const TableInCT* _o, const flatbuffers::rehasher_function_t *_rehasher) {
@@ -457,7 +457,7 @@ inline SecondTableInAT *SecondTableInA::UnPack(const flatbuffers::resolver_funct
 inline void SecondTableInA::UnPackTo(SecondTableInAT *_o, const flatbuffers::resolver_function_t *_resolver) const {
   (void)_o;
   (void)_resolver;
-  { auto _e = refer_to_c(); if (_e) _o->refer_to_c = flatbuffers::unique_ptr<NamespaceC::TableInCT>(_e->UnPack(_resolver)); }
+  { auto _e = refer_to_c(); if (_e) { if(_o->refer_to_c) { _e->UnPackTo(_o->refer_to_c.get(), _resolver); } else { _o->refer_to_c = flatbuffers::unique_ptr<NamespaceC::TableInCT>(_e->UnPack(_resolver)); } } }
 }
 
 inline flatbuffers::Offset<SecondTableInA> SecondTableInA::Pack(flatbuffers::FlatBufferBuilder &_fbb, const SecondTableInAT* _o, const flatbuffers::rehasher_function_t *_rehasher) {