diff --git a/CMakeLists.txt b/CMakeLists.txt
index f329385..5115480 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.25)
-project(blt-gp VERSION 0.0.137)
+project(blt-gp VERSION 0.0.138)
 
 include(CTest)
 
@@ -78,7 +78,7 @@ macro(blt_add_project name source type)
 
 #    set (passRegex "Pass" "Passed" "PASS" "PASSED")
 #    set (failRegex "WARN" "FAIL" "ERROR" "FATAL")
-    set (failRegex "\[WARN\]" "FAIL" "ERROR" "FATAL" "exception")
+    set (failRegex "\\[WARN\\]" "FAIL" "ERROR" "FATAL" "exception")
 
 #    set_property (TEST ${name} PROPERTY PASS_REGULAR_EXPRESSION "${passRegex}")
     set_property (TEST ${name} PROPERTY FAIL_REGULAR_EXPRESSION "${failRegex}")
diff --git a/include/blt/gp/fwdecl.h b/include/blt/gp/fwdecl.h
index ae5e769..c335344 100644
--- a/include/blt/gp/fwdecl.h
+++ b/include/blt/gp/fwdecl.h
@@ -52,13 +52,22 @@ namespace blt::gp
     
     namespace detail
     {
+        // requires operator[](bit_index), push_back, clear
+        using bitmask_t = std::vector<bool>;
+        
         class operator_storage_test;
         // context*, read stack, write stack
-        using callable_t = std::function<void(void*, stack_allocator&, stack_allocator&)>;
-        // to, from
-        using transfer_t = std::function<void(std::optional<std::reference_wrapper<stack_allocator>>, stack_allocator&)>;
+        using callable_t = std::function<void(void*, stack_allocator&, stack_allocator&, bitmask_t*)>;
         // debug function,
         using print_func_t = std::function<void(std::ostream&, stack_allocator&)>;
+        
+        enum class destroy_t
+        {
+            ARGS,
+            RETURN
+        };
+        
+        using destroy_func_t = std::function<void(destroy_t, bitmask_t* mask, stack_allocator&)>;
     }
     
 }
diff --git a/include/blt/gp/operations.h b/include/blt/gp/operations.h
index 839ba9f..126f625 100644
--- a/include/blt/gp/operations.h
+++ b/include/blt/gp/operations.h
@@ -102,16 +102,16 @@ namespace blt::gp
         }
         
         template<typename context = void, typename... NoCtxArgs>
-        void call_destructors_without_first(stack_allocator& read_allocator)
+        void call_destructors_without_first(stack_allocator& read_allocator, detail::bitmask_t* mask)
         {
             if constexpr (sizeof...(NoCtxArgs) > 0)
             {
-                read_allocator.call_destructors<detail::remove_cv_ref<NoCtxArgs>...>();
+                read_allocator.call_destructors<detail::remove_cv_ref<NoCtxArgs>...>(mask);
             }
         }
         
         template<typename Func, typename... ExtraArgs>
-        Return operator()(bool, Func&& func, stack_allocator& read_allocator, ExtraArgs&& ... args)
+        Return operator()(bool has_context, detail::bitmask_t* mask, Func&& func, stack_allocator& read_allocator, ExtraArgs&& ... args)
         {
             constexpr auto seq = std::make_integer_sequence<blt::u64, sizeof...(Args)>();
 #if BLT_DEBUG_LEVEL > 0
@@ -119,10 +119,10 @@ namespace blt::gp
             {
 #endif
             Return ret = exec_sequence_to_indices(std::forward<Func>(func), read_allocator, seq, std::forward<ExtraArgs>(args)...);
-            /*if (has_context)
-                call_destructors_without_first<Args...>(read_allocator);
+            if (has_context)
+                call_destructors_without_first<Args...>(read_allocator, mask);
             else
-                read_allocator.call_destructors<detail::remove_cv_ref<Args>...>();*/
+                read_allocator.call_destructors<detail::remove_cv_ref<Args>...>(mask);
             read_allocator.pop_bytes((stack_allocator::aligned_size<detail::remove_cv_ref<Args>>() + ...));
             return ret;
 #if BLT_DEBUG_LEVEL > 0
@@ -158,18 +158,18 @@ namespace blt::gp
             constexpr explicit operation_t(const Functor& functor, std::optional<std::string_view> name = {}): func(functor), name(name)
             {}
             
-            [[nodiscard]] constexpr inline Return operator()(stack_allocator& read_allocator) const
+            [[nodiscard]] constexpr inline Return operator()(stack_allocator& read_allocator, detail::bitmask_t* mask) const
             {
                 if constexpr (sizeof...(Args) == 0)
                 {
                     return func();
                 } else
                 {
-                    return call_with<Return, Args...>()(false, func, read_allocator);
+                    return call_with<Return, Args...>()(false, mask, func, read_allocator);
                 }
             }
             
-            [[nodiscard]] constexpr inline Return operator()(void* context, stack_allocator& read_allocator) const
+            [[nodiscard]] constexpr inline Return operator()(void* context, stack_allocator& read_allocator, detail::bitmask_t* mask) const
             {
                 // should be an impossible state
                 if constexpr (sizeof...(Args) == 0)
@@ -182,22 +182,22 @@ namespace blt::gp
                     return func(ctx_ref);
                 } else
                 {
-                    return call_without_first<Return, Args...>()(true, func, read_allocator, ctx_ref);
+                    return call_without_first<Return, Args...>()(true, mask, func, read_allocator, ctx_ref);
                 }
             }
             
             template<typename Context>
             [[nodiscard]] detail::callable_t make_callable() const
             {
-                return [this](void* context, stack_allocator& read_allocator, stack_allocator& write_allocator) {
+                return [this](void* context, stack_allocator& read_allocator, stack_allocator& write_allocator, detail::bitmask_t* mask) {
                     if constexpr (detail::is_same_v<Context, detail::remove_cv_ref<typename detail::first_arg<Args...>::type>>)
                     {
                         // first arg is context
-                        write_allocator.push(this->operator()(context, read_allocator));
+                        write_allocator.push(this->operator()(context, read_allocator, mask));
                     } else
                     {
                         // first arg isn't context
-                        write_allocator.push(this->operator()(read_allocator));
+                        write_allocator.push(this->operator()(read_allocator, mask));
                     }
                 };
             }
diff --git a/include/blt/gp/program.h b/include/blt/gp/program.h
index 390129e..6dce563 100644
--- a/include/blt/gp/program.h
+++ b/include/blt/gp/program.h
@@ -91,6 +91,7 @@ namespace blt::gp
         blt::hashset_t<operator_id> static_types;
         std::vector<operator_info> operators;
         std::vector<detail::print_func_t> print_funcs;
+        std::vector<detail::destroy_func_t> destroy_funcs;
         std::vector<std::optional<std::string_view>> names;
     };
     
@@ -135,13 +136,24 @@ namespace blt::gp
                 storage.print_funcs.push_back([&op](std::ostream& out, stack_allocator& stack) {
                     if constexpr (blt::meta::is_streamable_v<Return>)
                     {
-                        out << stack.pop<Return>();
+                        out << stack.from<Return>(0);
                         (void) (op); // remove warning
                     } else
                     {
                         out << "[Printing Value on '" << (op.get_name() ? *op.get_name() : "") << "' Not Supported!]";
                     }
                 });
+                storage.destroy_funcs.push_back([](detail::destroy_t type, detail::bitmask_t* mask, stack_allocator& alloc) {
+                    switch (type)
+                    {
+                        case detail::destroy_t::ARGS:
+                            alloc.call_destructors<Args...>(mask);
+                            break;
+                        case detail::destroy_t::RETURN:
+                            alloc.from<detail::remove_cv_ref<Return>>(0).drop();
+                            break;
+                    }
+                });
                 storage.names.push_back(op.get_name());
                 if (is_static)
                     storage.static_types.insert(operator_id);
@@ -374,6 +386,8 @@ namespace blt::gp
             void reset_program(type_id root_type, bool eval_fitness_now = true)
             {
                 current_generation = 0;
+                for (auto& pop : current_pop)
+                    pop.tree.drop(*this);
                 current_pop = config.pop_initializer.get().generate(
                         {*this, root_type, config.population_size, config.initial_min_tree_size, config.initial_max_tree_size});
                 if (eval_fitness_now)
@@ -484,6 +498,11 @@ namespace blt::gp
                 return storage.print_funcs[id];
             }
             
+            inline detail::destroy_func_t& get_destroy_func(operator_id id)
+            {
+                return storage.destroy_funcs[id];
+            }
+            
             inline std::optional<std::string_view> get_name(operator_id id)
             {
                 return storage.names[id];
@@ -521,6 +540,12 @@ namespace blt::gp
             
             ~gp_program()
             {
+                std::cout << ("Destroying Program!") << std::endl;
+                for (auto& pop : current_pop.get_individuals())
+                {
+                    pop.tree.drop(*this);
+                    pop = {};
+                }
                 thread_helper.lifetime_over = true;
                 thread_helper.barrier.notify_all();
                 thread_helper.thread_function_condition.notify_all();
diff --git a/include/blt/gp/stack.h b/include/blt/gp/stack.h
index e09aade..42dbac1 100644
--- a/include/blt/gp/stack.h
+++ b/include/blt/gp/stack.h
@@ -234,7 +234,7 @@ namespace blt::gp
                 NO_REF_T t = *reinterpret_cast<NO_REF_T*>(head->metadata.offset - TYPE_SIZE);
                 // call destructor
                 if constexpr (detail::has_func_drop_v<T>)
-                    call_drop<NO_REF_T>(0);
+                    call_drop<NO_REF_T>(0, 0, nullptr);
                 // move offset back
                 head->metadata.offset -= TYPE_SIZE;
                 // moving back allows us to allocate with other data, if there is room.
@@ -347,11 +347,22 @@ namespace blt::gp
             }
             
             template<typename... Args>
-            void call_destructors()
+            void call_destructors(detail::bitmask_t* mask)
             {
-                blt::size_t offset = (stack_allocator::aligned_size<NO_REF_T<Args>>() + ...) -
-                                     stack_allocator::aligned_size<NO_REF_T<typename blt::meta::arg_helper<Args...>::First>>();
-                ((call_drop<Args>(offset), offset -= stack_allocator::aligned_size<NO_REF_T<Args>>()), ...);
+                if constexpr (sizeof...(Args) > 0) {
+                    blt::size_t offset = (stack_allocator::aligned_size<NO_REF_T<Args>>() + ...) -
+                                         stack_allocator::aligned_size<NO_REF_T<typename blt::meta::arg_helper<Args...>::First>>();
+                    blt::size_t index = 0;
+                    if (mask != nullptr)
+                        index = mask->size() - sizeof...(Args);
+                    ((call_drop<Args>(offset, index, mask), offset -= stack_allocator::aligned_size<NO_REF_T<Args>>(), ++index), ...);
+                    if (mask != nullptr)
+                    {
+                        auto& mask_r = *mask;
+                        for (blt::size_t i = 0; i < sizeof...(Args); i++)
+                            mask_r.pop_back();
+                    }
+                }
             }
             
             [[nodiscard]] bool empty() const noexcept
@@ -552,10 +563,16 @@ namespace blt::gp
             };
             
             template<typename T>
-            inline void call_drop(blt::size_t offset)
+            inline void call_drop(blt::size_t offset, blt::size_t index, detail::bitmask_t* mask)
             {
                 if constexpr (detail::has_func_drop_v<T>)
                 {
+                    if (mask != nullptr)
+                    {
+                        auto& mask_r = *mask;
+                        if (!mask_r[index])
+                            return;
+                    }
                     from<NO_REF_T<T>>(offset).drop();
                 }
             }
diff --git a/include/blt/gp/tree.h b/include/blt/gp/tree.h
index 70644e8..adbe430 100644
--- a/include/blt/gp/tree.h
+++ b/include/blt/gp/tree.h
@@ -60,6 +60,31 @@ namespace blt::gp
     {
             using iter_type = std::vector<op_container_t>::const_iterator;
         public:
+            tree_t(): reference_counter(new std::atomic_int64_t(1))
+            {}
+            
+            tree_t(const tree_t& copy): operations(copy.operations), values(copy.values), reference_counter(copy.reference_counter)
+            {
+                reference_counter->operator++();
+            }
+            
+            tree_t(tree_t&& move) noexcept:
+                    operations(std::move(move.operations)), values(std::move(move.values)), reference_counter(move.reference_counter)
+            {
+                move.reference_counter = nullptr;
+            }
+            
+            tree_t& operator=(const tree_t& copy) = delete;
+            
+            tree_t& operator=(tree_t&& move) noexcept
+            {
+                operations = std::exchange(operations, std::move(move.operations));
+                values = std::exchange(values, std::move(move.values));
+                reference_counter = std::exchange(reference_counter, move.reference_counter);
+                return *this;
+            }
+            
+            
             [[nodiscard]] inline std::vector<op_container_t>& get_operations()
             {
                 return operations;
@@ -146,10 +171,22 @@ namespace blt::gp
             {
                 return total_value_bytes(operations.begin(), operations.end());
             }
+            
+            void drop(gp_program& program);
+            
+            ~tree_t()
+            {
+                if (reference_counter == nullptr)
+                    return;
+                reference_counter->operator--();
+                if (*reference_counter == 0)
+                    delete reference_counter;
+            }
         
         private:
             std::vector<op_container_t> operations;
             blt::gp::stack_allocator values;
+            std::atomic_int64_t* reference_counter;
     };
     
     struct fitness_t
diff --git a/lib/blt b/lib/blt
index 92300bc..644f426 160000
--- a/lib/blt
+++ b/lib/blt
@@ -1 +1 @@
-Subproject commit 92300bc6a29927f5354d516df76ad40be7fca868
+Subproject commit 644f42684320edc95f9fd5fc3b203bda3c4e6633
diff --git a/src/generators.cpp b/src/generators.cpp
index 2872460..1443f07 100644
--- a/src/generators.cpp
+++ b/src/generators.cpp
@@ -71,7 +71,7 @@ namespace blt::gp
             
             if (args.program.is_static(top.id))
             {
-                info.function(nullptr, tree.get_values(), tree.get_values());
+                info.function(nullptr, tree.get_values(), tree.get_values(), nullptr);
                 continue;
             }
             
diff --git a/src/tree.cpp b/src/tree.cpp
index 82d9c96..a9de1f2 100644
--- a/src/tree.cpp
+++ b/src/tree.cpp
@@ -24,7 +24,8 @@
 
 namespace blt::gp
 {
-    inline auto empty_callable = detail::callable_t([](void*, stack_allocator&, stack_allocator&) { BLT_ABORT("This should never be called!"); });
+    inline auto empty_callable = detail::callable_t(
+            [](void*, stack_allocator&, stack_allocator&, detail::bitmask_t*) { BLT_ABORT("This should never be called!"); });
     
     evaluation_context tree_t::evaluate(void* context) const
     {
@@ -47,15 +48,19 @@ namespace blt::gp
         
         auto value_stack = values;
         auto& values_process = results.values;
+        static thread_local detail::bitmask_t bitfield;
+        bitfield.clear();
         
         for (const auto& operation : blt::reverse_iterate(operations.begin(), operations.end()))
         {
             if (operation.is_value)
             {
                 value_stack.transfer_bytes(values_process, operation.type_size);
+                bitfield.push_back(false);
                 continue;
             }
-            operation.func(context, values_process, values_process);
+            operation.func(context, values_process, values_process, &bitfield);
+            bitfield.push_back(true);
         }
         
         return results;
@@ -222,6 +227,8 @@ namespace blt::gp
     
     bool tree_t::check(gp_program& program, void* context) const
     {
+        static thread_local detail::bitmask_t bitfield;
+        bitfield.clear();
         blt::size_t bytes_expected = 0;
         auto bytes_size = values.size().total_used_bytes;
         
@@ -255,12 +262,14 @@ namespace blt::gp
             {
                 value_stack.transfer_bytes(values_process, operation.type_size);
                 total_produced += stack_allocator::aligned_size(operation.type_size);
+                bitfield.push_back(false);
                 continue;
             }
             auto& info = program.get_operator_info(operation.id);
             for (auto& arg : info.argument_types)
                 total_consumed += stack_allocator::aligned_size(program.get_typesystem().get_type(arg).size());
-            operation.func(context, values_process, values_process);
+            operation.func(context, values_process, values_process, &bitfield);
+            bitfield.push_back(true);
             total_produced += stack_allocator::aligned_size(program.get_typesystem().get_type(info.return_type).size());
         }
         
@@ -276,4 +285,38 @@ namespace blt::gp
         }
         return true;
     }
+    
+    void tree_t::drop(gp_program& program)
+    {
+        return;
+        if (values.empty())
+            return;
+        std::cout << "---- NEW TREE ---- References " << *reference_counter << " ----" << std::endl;
+        if (reference_counter->load() > 1)
+            return;
+        static blt::hashset_t<blt::size_t> sets;
+        while (!operations.empty())
+        {
+            auto operation = operations.back();
+            if (operation.is_value)
+            {
+                struct hello
+                {
+                    float* f;
+                    blt::size_t i;
+                };
+                auto h = values.from<hello>(0);
+                if (sets.find(h.i) != sets.end())
+                    std::cout << "HEY ASSHOLE Duplicate Value " << h.i << std::endl;
+                else
+                {
+                    std::cout << "Destroying Value " << h.i << std::endl;
+                    sets.insert(h.i);
+                }
+                program.get_destroy_func(operation.id)(detail::destroy_t::RETURN, nullptr, values);
+                values.pop_bytes(static_cast<blt::ptrdiff_t>(stack_allocator::aligned_size(operation.type_size)));
+            }
+            operations.pop_back();
+        }
+    }
 }
\ No newline at end of file
diff --git a/tests/destructor_test.cpp b/tests/destructor_test.cpp
index ee1677d..5bf05b8 100644
--- a/tests/destructor_test.cpp
+++ b/tests/destructor_test.cpp
@@ -53,41 +53,47 @@ class move_float
         move_float(): f(new float()), assignment(++last_value)
         {
             constructions++;
-            BLT_TRACE("Value %ld Default Constructed", assignment);
+            //BLT_TRACE("Value %ld Default Constructed", assignment);
         }
         
         explicit move_float(float f): f(new float(f)), assignment(++last_value)
         {
             constructions++;
-            BLT_TRACE("Value %ld Constructed", assignment);
+            //BLT_TRACE("Value %ld Constructed", assignment);
         }
         
         explicit operator float() const
         {
-            BLT_TRACE("Using value %ld", assignment);
+            //BLT_TRACE("Using value %ld", assignment);
             return *f;
         }
         
         [[nodiscard]] float get() const
         {
-            BLT_TRACE("Using value %ld", assignment);
+            //BLT_TRACE("Using value %ld", assignment);
             return *f;
         }
         
         float operator*() const
         {
-            BLT_TRACE("Using value %ld", assignment);
+            //BLT_TRACE("Using value %ld", assignment);
             return *f;
         }
         
         void drop() // NOLINT
         {
-            BLT_TRACE("Drop Called On %ld", assignment);
+            //BLT_TRACE("Drop Called On %ld", assignment);
             delete f;
             f = nullptr;
             destructions++;
         }
-    
+        
+        friend std::ostream& operator<<(std::ostream& stream, const move_float& e)
+        {
+            stream << *e;
+            return stream;
+        }
+        
     private:
         float* f = nullptr;
         blt::size_t assignment;
@@ -106,13 +112,13 @@ std::array<context, 200> fitness_cases;
 blt::gp::prog_config_t config = blt::gp::prog_config_t()
         .set_initial_min_tree_size(2)
         .set_initial_max_tree_size(6)
-        .set_elite_count(2)
+        .set_elite_count(0)
         .set_crossover_chance(0.9)
         .set_mutation_chance(0.1)
         .set_reproduction_chance(0)
-        .set_max_generations(1)
-        .set_pop_size(1)
-        .set_thread_count(1);
+        .set_max_generations(5)
+        .set_pop_size(500)
+        .set_thread_count(0);
 
 blt::gp::type_provider type_system;
 blt::gp::gp_program program{type_system, SEED, config};
@@ -137,7 +143,10 @@ constexpr auto fitness_function = [](blt::gp::tree_t& current_tree, blt::gp::fit
     constexpr double value_cutoff = 1.e15;
     for (auto& fitness_case : fitness_cases)
     {
-        auto diff = std::abs(fitness_case.y - *current_tree.get_evaluation_value<move_float>(&fitness_case));
+        auto ctx = current_tree.evaluate(&fitness_case);
+        auto diff = std::abs(fitness_case.y - *current_tree.get_evaluation_ref<move_float>(ctx));
+        // this will call the drop function.
+        current_tree.get_evaluation_value<move_float>(ctx);
         if (diff < value_cutoff)
         {
             fitness.raw_fitness += diff;
@@ -211,7 +220,7 @@ int main()
     
     BLT_END_INTERVAL("Symbolic Regression", "Main");
     
-    auto best = program.get_best_individuals<3>();
+    auto best = program.get_best_individuals<1>();
     
     BLT_INFO("Best approximations:");
     for (auto& i_ref : best)
diff --git a/tests/evaluation_tests.cpp b/tests/evaluation_tests.cpp
index 4d88428..598710f 100644
--- a/tests/evaluation_tests.cpp
+++ b/tests/evaluation_tests.cpp
@@ -63,7 +63,7 @@ blt::gp::op_container_t make_container(blt::gp::operator_id id)
 
 blt::gp::op_container_t make_value(const blt::gp::type& id)
 {
-    static blt::gp::detail::callable_t empty([](void*, blt::gp::stack_allocator&, blt::gp::stack_allocator&) {});
+    static blt::gp::detail::callable_t empty([](void*, blt::gp::stack_allocator&, blt::gp::stack_allocator&, blt::gp::detail::bitmask_t*) {});
     return {empty, id.size(), 0, true};
 }
 
diff --git a/tests/gp_test_1.cpp b/tests/gp_test_1.cpp
index 641ea8b..e1fe9be 100644
--- a/tests/gp_test_1.cpp
+++ b/tests/gp_test_1.cpp
@@ -424,7 +424,7 @@ int main()
         return f + g;
     });
     
-    std::cout << silly_op(alloc) << std::endl;
+    std::cout << silly_op(alloc, nullptr) << std::endl;
     
     std::cout << "Is empty? " << alloc.empty() << std::endl;
     
@@ -456,15 +456,15 @@ int main()
     context hello{5, 10};
     
     alloc.push(1.153f);
-    de[0](static_cast<void*>(&hello), alloc, alloc);
+    de[0](static_cast<void*>(&hello), alloc, alloc, nullptr);
     BLT_TRACE("first value: %f", alloc.pop<float>());
     
-    de[1](static_cast<void*>(&hello), alloc, alloc);
+    de[1](static_cast<void*>(&hello), alloc, alloc, nullptr);
     BLT_TRACE("second value: %f", alloc.pop<float>());
     
     alloc.push(1.0f);
     alloc.push(52.213f);
-    de[2](static_cast<void*>(&hello), alloc, alloc);
+    de[2](static_cast<void*>(&hello), alloc, alloc, nullptr);
     BLT_TRACE("third value: %f", alloc.pop<float>());
     
     //auto* pointer = static_cast<void*>(head->metadata.offset);
@@ -482,7 +482,7 @@ int main()
     
     //blt::span<void*, 3> spv{arr};
     
-    std::cout << silly_op.operator()(alloc) << std::endl;
+    std::cout << silly_op.operator()(alloc, nullptr) << std::endl;
     
     std::cout << "Hello World!" << std::endl;
     
diff --git a/tests/stack_tests.cpp b/tests/stack_tests.cpp
index effdf1c..10e9995 100644
--- a/tests/stack_tests.cpp
+++ b/tests/stack_tests.cpp
@@ -301,7 +301,7 @@ void test_basic()
         stack.push(50.0f);
         stack.push(10.0f);
         BLT_TRACE_STREAM << stack.size() << "\n";
-        basic_2.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack);
+        basic_2.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack, nullptr);
         BLT_TRACE_STREAM << stack.size() << "\n";
         auto val = stack.pop<float>();
         RUN_TEST(val != 60.000000f, stack, "Basic 2 Test Passed", "Basic 2 Test Failed. Unexpected value produced '%lf'", val);
@@ -317,7 +317,7 @@ void test_basic()
         auto size = stack.size();
         BLT_TRACE_STREAM << size << "\n";
         BLT_ASSERT(size.blocks > 1 && "Stack doesn't have more than one block!");
-        basic_2.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack);
+        basic_2.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack, nullptr);
         BLT_TRACE_STREAM << stack.size() << "\n";
         auto val = stack.pop<float>();
         stack.pop<std::array<blt::u8, blt::gp::stack_allocator::page_size_no_block() - sizeof(float)>>();
@@ -338,7 +338,7 @@ void test_mixed()
         stack.push(false);
         
         BLT_TRACE_STREAM << stack.size() << "\n";
-        basic_mixed_4.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack);
+        basic_mixed_4.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack, nullptr);
         BLT_TRACE_STREAM << stack.size() << "\n";
         auto val = stack.pop<float>();
         RUN_TEST(val != 50.000000f, stack, "Mixed 4 Test Passed", "Mixed 4 Test Failed. Unexpected value produced '%lf'", val);
@@ -356,7 +356,7 @@ void test_mixed()
         auto size = stack.size();
         BLT_TRACE_STREAM << size << "\n";
         BLT_ASSERT(size.blocks > 1 && "Stack doesn't have more than one block!");
-        basic_mixed_4.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack);
+        basic_mixed_4.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack, nullptr);
         BLT_TRACE_STREAM << stack.size() << "\n";
         auto val = stack.pop<float>();
         stack.pop<std::array<blt::u8, blt::gp::stack_allocator::page_size_no_block() - sizeof(float)>>();
@@ -376,7 +376,7 @@ void test_large_256()
         stack.push(69.420f);
         
         BLT_TRACE_STREAM << stack.size() << "\n";
-        large_256_basic_3.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack);
+        large_256_basic_3.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack, nullptr);
         BLT_TRACE_STREAM << stack.size() << "\n";
         auto val = stack.pop<large_256>();
         RUN_TEST(!compare(val, base_256), stack, "Large 256 3 Test Passed", "Large 256 3 Test Failed. Unexpected value produced '%lf'", val);
@@ -393,7 +393,7 @@ void test_large_256()
         auto size = stack.size();
         BLT_TRACE_STREAM << size << "\n";
         BLT_ASSERT(size.blocks > 1 && "Stack doesn't have more than one block!");
-        large_256_basic_3.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack);
+        large_256_basic_3.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack, nullptr);
         BLT_TRACE_STREAM << stack.size() << "\n";
         auto val = stack.pop<large_256>();
         stack.pop<std::array<blt::u8, blt::gp::stack_allocator::page_size_no_block() - sizeof(large_256)>>();
@@ -412,7 +412,7 @@ void test_large_4096()
         stack.push(33.0f);
         stack.push(true);
         BLT_TRACE_STREAM << stack.size() << "\n";
-        large_4096_basic_3b.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack);
+        large_4096_basic_3b.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack, nullptr);
         BLT_TRACE_STREAM << stack.size() << "\n";
         auto val = stack.pop<large_4096>();
         RUN_TEST(!compare(val, base_4096), stack, "Large 4096 3 Test Passed", "Large 4096 3 Test Failed. Unexpected value produced '%lf'", val);
@@ -428,7 +428,7 @@ void test_large_4096()
         auto size = stack.size();
         BLT_TRACE_STREAM << size << "\n";
         BLT_ASSERT(size.blocks > 1 && "Stack doesn't have more than one block!");
-        large_4096_basic_3b.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack);
+        large_4096_basic_3b.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack, nullptr);
         BLT_TRACE_STREAM << stack.size() << "\n";
         auto val = stack.pop<large_4096>();
         RUN_TEST(!compare(val, base_4096), stack, "Large 4096 3 Boundary Test Passed", "Large 4096 3 Test Failed. Unexpected value produced '%lf'", val);
@@ -446,7 +446,7 @@ void test_large_18290()
         stack.push(-2543.0f);
         stack.push(true);
         BLT_TRACE_STREAM << stack.size() << "\n";
-        large_18290_basic_3b.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack);
+        large_18290_basic_3b.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack, nullptr);
         BLT_TRACE_STREAM << stack.size() << "\n";
         auto val = stack.pop<large_18290>();
         RUN_TEST(!compare(val, base_18290), stack, "Large 18290 3 Test Passed", "Large 4096 3 Test Failed. Unexpected value produced '%lf'", val);
@@ -463,7 +463,7 @@ void test_large_18290()
         auto size = stack.size();
         BLT_TRACE_STREAM << size << "\n";
         BLT_ASSERT(size.blocks > 1 && "Stack doesn't have more than one block!");
-        large_18290_basic_3b.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack);
+        large_18290_basic_3b.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack, nullptr);
         BLT_TRACE_STREAM << stack.size() << "\n";
         auto val = stack.pop<large_18290>();
         stack.pop<std::array<blt::u8, 20480 - 18290 - blt::gp::stack_allocator::block_size()>>();
@@ -479,12 +479,12 @@ void test_large_18290()
         stack.push(true);
         auto size = stack.size();
         BLT_TRACE_STREAM << size << "\n";
-        large_18290_basic_3b.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack);
+        large_18290_basic_3b.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack, nullptr);
         BLT_TRACE_STREAM << stack.size() << "\n";
         stack.push(-2543.0f);
         stack.push(true);
         BLT_TRACE_STREAM << stack.size() << "\n";
-        large_18290_basic_3b.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack);
+        large_18290_basic_3b.make_callable<blt::gp::detail::empty_t>()(nullptr, stack, stack, nullptr);
         BLT_TRACE_STREAM << stack.size() << "\n";
         auto val = stack.pop<large_18290>();
         RUN_TEST(!compare(val, base_18290), stack, "Large 18290 3 Boundary Test Passed", "Large 4096 3 Test Failed. Unexpected value produced '%lf'", val);