Fix dangling and reassigned Variants

This commit addresses multiple issues with `Variant`s that point to an `Object`
which is later released, when it's tried to be accessed again.

Formerly, **while running on the debugger the system would check if the instance id was
still valid** to print warnings or return special values. Some cases weren't being
warned about whatsoever.

Also, a newly allocated `Object` could happen to be allocated at the same memory
address of an old one, making cases of use hard to find and having **`Variant`s pointing
to the old one magically reassigned to the new**.

This commit makes the engine realize all these situations **under debugging**
so you can detect and fix them. Running without a debugger attached will still
behave as it always did.

Also the warning messages have been extended and made clearer.

All that said, in the name of performance there's still one possible case of undefined
behavior: in multithreaded scripts there would be a race condition between a thread freeing
an `Object` and another one trying to operate on it. The latter may not realize the
`Object` has been freed soon enough. But that's a case of bad scripting that was never
supported anyway.

core/object.cpp

@@ -33,6 +33,7 @@
 #include "core/class_db.h"
 #include "core/core_string_names.h"
 #include "core/message_queue.h"
+#include "core/object_rc.h"
 #include "core/os/os.h"
 #include "core/print_string.h"
 #include "core/resource.h"
@@ -968,6 +969,37 @@ void Object::cancel_delete() {
 	_predelete_ok = true;
 }
 
+#ifdef DEBUG_ENABLED
+ObjectRC *Object::_use_rc() {
+
+	// The RC object is lazily created the first time it's requested;
+	// that way, there's no need to allocate and release it at all if this Object
+	// is not being referred by any Variant at all.
+
+	// Although when dealing with Objects from multiple threads some locking
+	// mechanism should be used, this at least makes safe the case of first
+	// assignment.
+
+	ObjectRC *rc = nullptr;
+	ObjectRC *const creating = reinterpret_cast<ObjectRC *>(1);
+	if (unlikely(_rc.compare_exchange_strong(rc, creating, std::memory_order_acq_rel))) {
+		// Not created yet
+		rc = memnew(ObjectRC(this));
+		_rc.store(rc, std::memory_order_release);
+		return rc;
+	}
+
+	// Spin-wait until we know it's created (or just return if it's already created)
+	for (;;) {
+		if (likely(rc != creating)) {
+			rc->increment();
+			return rc;
+		}
+		rc = _rc.load(std::memory_order_acquire);
+	}
+}
+#endif
+
 void Object::set_script_and_instance(const RefPtr &p_script, ScriptInstance *p_instance) {
 
 	//this function is not meant to be used in any of these ways
@@ -1944,6 +1976,9 @@ Object::Object() {
 	instance_binding_count = 0;
 	memset(_script_instance_bindings, 0, sizeof(void *) * MAX_SCRIPT_INSTANCE_BINDINGS);
 	script_instance = NULL;
+#ifdef DEBUG_ENABLED
+	_rc.store(nullptr, std::memory_order_release);
+#endif
 #ifdef TOOLS_ENABLED
 
 	_edited = false;
@@ -1957,6 +1992,15 @@ Object::Object() {
 
 Object::~Object() {
 
+#ifdef DEBUG_ENABLED
+	ObjectRC *rc = _rc.load(std::memory_order_acquire);
+	if (rc) {
+		if (rc->invalidate()) {
+			memfree(rc);
+		}
+	}
+#endif
+
 	if (script_instance)
 		memdelete(script_instance);
 	script_instance = NULL;

core/object.h

@@ -34,11 +34,16 @@
 #include "core/hash_map.h"
 #include "core/list.h"
 #include "core/map.h"
+#include "core/object_id.h"
 #include "core/os/rw_lock.h"
 #include "core/set.h"
 #include "core/variant.h"
 #include "core/vmap.h"
 
+#ifdef DEBUG_ENABLED
+#include <atomic> // For ObjectRC*
+#endif
+
 #define VARIANT_ARG_LIST const Variant &p_arg1 = Variant(), const Variant &p_arg2 = Variant(), const Variant &p_arg3 = Variant(), const Variant &p_arg4 = Variant(), const Variant &p_arg5 = Variant()
 #define VARIANT_ARG_PASS p_arg1, p_arg2, p_arg3, p_arg4, p_arg5
 #define VARIANT_ARG_DECLARE const Variant &p_arg1, const Variant &p_arg2, const Variant &p_arg3, const Variant &p_arg4, const Variant &p_arg5
@@ -397,7 +402,7 @@ public:                                                        \
 private:
 
 class ScriptInstance;
-typedef uint64_t ObjectID;
+class ObjectRC;
 
 class Object {
 public:
@@ -477,6 +482,9 @@ private:
 	int _predelete_ok;
 	Set<Object *> change_receptors;
 	ObjectID _instance_id;
+#ifdef DEBUG_ENABLED
+	std::atomic<ObjectRC *> _rc;
+#endif
 	bool _predelete();
 	void _postinitialize();
 	bool _can_translate;
@@ -587,6 +595,10 @@ public:
 		return &ptr;
 	}
 
+#ifdef DEBUG_ENABLED
+	ObjectRC *_use_rc();
+#endif
+
 	bool _is_gpl_reversed() const { return false; }
 
 	_FORCE_INLINE_ ObjectID get_instance_id() const { return _instance_id; }

core/object_id.h

@@ -0,0 +1,38 @@
+/*************************************************************************/
+/*  object_rc.h                                                          */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef OBJECTID_H
+#define OBJECTID_H
+
+#include "core/int_types.h"
+
+typedef uint64_t ObjectID;
+
+#endif

core/object_rc.h

@@ -0,0 +1,75 @@
+/*************************************************************************/
+/*  object_rc.h                                                          */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef OBJECTRC_H
+#define OBJECTRC_H
+
+#ifdef DEBUG_ENABLED
+
+#include "core/os/memory.h"
+#include "core/typedefs.h"
+
+#include <atomic>
+
+class Object;
+
+// Used to track Variants pointing to a non-Reference Object
+class ObjectRC {
+	std::atomic<Object *> _ptr;
+	std::atomic<uint32_t> _users;
+
+public:
+	_FORCE_INLINE_ void increment() {
+		_users.fetch_add(1, std::memory_order_relaxed);
+	}
+
+	_FORCE_INLINE_ bool decrement() {
+		return _users.fetch_sub(1, std::memory_order_relaxed) == 1;
+	}
+
+	_FORCE_INLINE_ bool invalidate() {
+		_ptr.store(nullptr, std::memory_order_release);
+		return decrement();
+	}
+
+	_FORCE_INLINE_ Object *get_ptr() {
+		return _ptr.load(std::memory_order_acquire);
+	}
+
+	_FORCE_INLINE_ ObjectRC(Object *p_object) {
+		// 1 (the Object) + 1 (the first user)
+		_users.store(2, std::memory_order_relaxed);
+		_ptr.store(p_object, std::memory_order_release);
+	}
+};
+
+#endif
+
+#endif

core/variant.cpp

@@ -33,6 +33,7 @@
 #include "core/core_string_names.h"
 #include "core/io/marshalls.h"
 #include "core/math/math_funcs.h"
+#include "core/object_rc.h"
 #include "core/print_string.h"
 #include "core/resource.h"
 #include "core/variant_parser.h"
@@ -790,7 +791,7 @@ bool Variant::is_zero() const {
 		} break;
 		case OBJECT: {
 
-			return _get_obj().obj == NULL;
+			return _OBJ_PTR(*this) == NULL;
 		} break;
 		case NODE_PATH: {
 
@@ -1000,6 +1001,11 @@ void Variant::reference(const Variant &p_variant) {
 		case OBJECT: {
 
 			memnew_placement(_data._mem, ObjData(p_variant._get_obj()));
+#ifdef DEBUG_ENABLED
+			if (_get_obj().rc) {
+				_get_obj().rc->increment();
+			}
+#endif
 		} break;
 		case NODE_PATH: {
 
@@ -1114,8 +1120,19 @@ void Variant::clear() {
 		} break;
 		case OBJECT: {
 
+#ifdef DEBUG_ENABLED
+			if (_get_obj().rc) {
+				if (_get_obj().rc->decrement()) {
+					memfree(_get_obj().rc);
+				}
+				_get_obj().instance_id = 0;
+			} else {
+				_get_obj().ref.unref();
+			}
+#else
 			_get_obj().obj = NULL;
 			_get_obj().ref.unref();
+#endif
 		} break;
 		case _RID: {
 			// not much need probably
@@ -1580,19 +1597,17 @@ String Variant::stringify(List<const void *> &stack) const {
 		} break;
 		case OBJECT: {
 
-			if (_get_obj().obj) {
+			Object *obj = _OBJ_PTR(*this);
+			if (obj) {
+				return obj->to_string();
+			} else {
 #ifdef DEBUG_ENABLED
-				if (ScriptDebugger::get_singleton() && _get_obj().ref.is_null()) {
-					//only if debugging!
-					if (!ObjectDB::instance_validate(_get_obj().obj)) {
-						return "[Deleted Object]";
-					};
-				};
+				if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+					return "[Deleted Object]";
+				}
 #endif
-				return _get_obj().obj->to_string();
-			} else
 				return "[Object:null]";
-
+			}
 		} break;
 		default: {
 			return "[" + get_type_name(type) + "]";
@@ -1741,22 +1756,33 @@ Variant::operator RefPtr() const {
 
 Variant::operator RID() const {
 
-	if (type == _RID)
+	if (type == _RID) {
 		return *reinterpret_cast<const RID *>(_data._mem);
-	else if (type == OBJECT && !_get_obj().ref.is_null()) {
-		return _get_obj().ref.get_rid();
-	} else if (type == OBJECT && _get_obj().obj) {
+	} else if (type == OBJECT) {
+		if (!_get_obj().ref.is_null()) {
+			return _get_obj().ref.get_rid();
+		} else {
 #ifdef DEBUG_ENABLED
-		if (ScriptDebugger::get_singleton()) {
-			ERR_FAIL_COND_V_MSG(!ObjectDB::instance_validate(_get_obj().obj), RID(), "Invalid pointer (object was deleted).");
-		};
+			Object *obj = _get_obj().rc->get_ptr();
+			if (unlikely(!obj)) {
+				if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+					WARN_PRINT("Attempted get RID on a deleted object.");
+				}
+			}
+#else
+			Object *obj = _get_obj().obj;
+			if (unlikely(!obj)) {
+				return RID();
+			}
 #endif
-		Variant::CallError ce;
-		Variant ret = _get_obj().obj->call(CoreStringNames::get_singleton()->get_rid, NULL, 0, ce);
-		if (ce.error == Variant::CallError::CALL_OK && ret.get_type() == Variant::_RID) {
-			return ret;
+			Variant::CallError ce;
+			Variant ret = obj->call(CoreStringNames::get_singleton()->get_rid, NULL, 0, ce);
+			if (ce.error == Variant::CallError::CALL_OK && ret.get_type() == Variant::_RID) {
+				return ret;
+			} else {
+				return RID();
+			}
 		}
-		return RID();
 	} else {
 		return RID();
 	}
@@ -1765,23 +1791,33 @@ Variant::operator RID() const {
 Variant::operator Object *() const {
 
 	if (type == OBJECT)
-		return _get_obj().obj;
+		return _OBJ_PTR(*this);
 	else
 		return NULL;
 }
 Variant::operator Node *() const {
 
-	if (type == OBJECT)
-		return Object::cast_to<Node>(_get_obj().obj);
-	else
-		return NULL;
+	if (type == OBJECT) {
+#ifdef DEBUG_ENABLED
+		Object *obj = _get_obj().rc ? _get_obj().rc->get_ptr() : NULL;
+#else
+		Object *obj = _get_obj().obj;
+#endif
+		return Object::cast_to<Node>(obj);
+	}
+	return NULL;
 }
 Variant::operator Control *() const {
 
-	if (type == OBJECT)
-		return Object::cast_to<Control>(_get_obj().obj);
-	else
-		return NULL;
+	if (type == OBJECT) {
+#ifdef DEBUG_ENABLED
+		Object *obj = _get_obj().rc ? _get_obj().rc->get_ptr() : NULL;
+#else
+		Object *obj = _get_obj().obj;
+#endif
+		return Object::cast_to<Control>(obj);
+	}
+	return NULL;
 }
 
 Variant::operator Dictionary() const {
@@ -2280,8 +2316,13 @@ Variant::Variant(const RefPtr &p_resource) {
 
 	type = OBJECT;
 	memnew_placement(_data._mem, ObjData);
+#ifdef DEBUG_ENABLED
+	_get_obj().rc = NULL;
+	_get_obj().instance_id = 0;
+#else
 	REF *ref = reinterpret_cast<REF *>(p_resource.get_data());
 	_get_obj().obj = ref->ptr();
+#endif
 	_get_obj().ref = p_resource;
 }
 
@@ -2296,7 +2337,12 @@ Variant::Variant(const Object *p_object) {
 	type = OBJECT;
 
 	memnew_placement(_data._mem, ObjData);
+#ifdef DEBUG_ENABLED
+	_get_obj().rc = p_object ? const_cast<Object *>(p_object)->_use_rc() : NULL;
+	_get_obj().instance_id = p_object ? p_object->get_instance_id() : 0;
+#else
 	_get_obj().obj = const_cast<Object *>(p_object);
+#endif
 }
 
 Variant::Variant(const Dictionary &p_dictionary) {
@@ -2608,6 +2654,11 @@ void Variant::operator=(const Variant &p_variant) {
 		case OBJECT: {
 
 			*reinterpret_cast<ObjData *>(_data._mem) = p_variant._get_obj();
+#ifdef DEBUG_ENABLED
+			if (_get_obj().rc) {
+				_get_obj().rc->increment();
+			}
+#endif
 		} break;
 		case NODE_PATH: {
 
@@ -2805,7 +2856,7 @@ uint32_t Variant::hash() const {
 		} break;
 		case OBJECT: {
 
-			return hash_djb2_one_64(make_uint64_t(_get_obj().obj));
+			return hash_djb2_one_64(make_uint64_t(_OBJ_PTR(*this)));
 		} break;
 		case NODE_PATH: {
 

core/variant.h

@@ -44,13 +44,14 @@
 #include "core/math/transform_2d.h"
 #include "core/math/vector3.h"
 #include "core/node_path.h"
+#include "core/object_id.h"
 #include "core/pool_vector.h"
 #include "core/ref_ptr.h"
 #include "core/rid.h"
 #include "core/ustring.h"
 
-class RefPtr;
 class Object;
+class ObjectRC;
 class Node; // helper
 class Control; // helper
 
@@ -72,6 +73,13 @@ typedef PoolVector<Color> PoolColorArray;
 #define GCC_ALIGNED_8
 #endif
 
+#ifdef DEBUG_ENABLED
+// Ideally, an inline member of ObjectRC, but would cause circular includes
+#define _OBJ_PTR(m_variant) ((m_variant)._get_obj().rc ? (m_variant)._get_obj().rc->get_ptr() : reinterpret_cast<Ref<Reference> *>((m_variant)._get_obj().ref.get_data())->ptr())
+#else
+#define _OBJ_PTR(m_variant) ((m_variant)._get_obj().obj)
+#endif
+
 class Variant {
 public:
 	// If this changes the table in variant_op must be updated
@@ -127,7 +135,21 @@ private:
 
 	struct ObjData {
 
+#ifdef DEBUG_ENABLED
+		// Will be null for every type deriving from Reference as they have their
+		// own reference count mechanism
+		ObjectRC *rc;
+		// This is for allowing debug build to check for instance ID validity,
+		// so warnings are shown in debug builds when a stray Variant (one pointing
+		// to a released Object) would have happened.
+		// If it's zero, that means the Variant is has a legit null object value,
+		// thus not needing instance id validation.
+		ObjectID instance_id;
+#else
 		Object *obj;
+#endif
+		// Always initialized, but will be null if the Ref<> assigned was null
+		// or this Variant is not even holding a Reference-derived object
 		RefPtr ref;
 	};
 

core/variant_call.cpp

@@ -35,6 +35,7 @@
 #include "core/crypto/crypto_core.h"
 #include "core/io/compression.h"
 #include "core/object.h"
+#include "core/object_rc.h"
 #include "core/os/os.h"
 #include "core/script_language.h"
 
@@ -1094,22 +1095,18 @@ void Variant::call_ptr(const StringName &p_method, const Variant **p_args, int p
 
 	if (type == Variant::OBJECT) {
 		//call object
-		Object *obj = _get_obj().obj;
+		Object *obj = _OBJ_PTR(*this);
 		if (!obj) {
-			r_error.error = CallError::CALL_ERROR_INSTANCE_IS_NULL;
-			return;
-		}
 #ifdef DEBUG_ENABLED
-		if (ScriptDebugger::get_singleton() && _get_obj().ref.is_null()) {
-			//only if debugging!
-			if (!ObjectDB::instance_validate(obj)) {
-				r_error.error = CallError::CALL_ERROR_INSTANCE_IS_NULL;
-				return;
+			if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+				WARN_PRINT("Attempted call on stray pointer object.");
 			}
+#endif
+			r_error.error = CallError::CALL_ERROR_INSTANCE_IS_NULL;
+			return;
 		}
 
-#endif
-		ret = _get_obj().obj->call(p_method, p_args, p_argcount, r_error);
+		ret = obj->call(p_method, p_args, p_argcount, r_error);
 
 		//else if (type==Variant::METHOD) {
 
@@ -1275,18 +1272,16 @@ Variant Variant::construct(const Variant::Type p_type, const Variant **p_args, i
 bool Variant::has_method(const StringName &p_method) const {
 
 	if (type == OBJECT) {
-		Object *obj = operator Object *();
-		if (!obj)
-			return false;
-#ifdef DEBUG_ENABLED
-		if (ScriptDebugger::get_singleton()) {
-			if (ObjectDB::instance_validate(obj)) {
-#endif
-				return obj->has_method(p_method);
+		Object *obj = _OBJ_PTR(*this);
+		if (!obj) {
 #ifdef DEBUG_ENABLED
+			if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+				WARN_PRINT("Attempted method check on stray pointer object.");
 			}
-		}
 #endif
+			return false;
+		}
+		return obj->has_method(p_method);
 	}
 
 	const _VariantCall::TypeFunc &tf = _VariantCall::type_funcs[type];

core/variant_op.cpp

@@ -32,6 +32,7 @@
 
 #include "core/core_string_names.h"
 #include "core/object.h"
+#include "core/object_rc.h"
 #include "core/script_language.h"
 
 #define CASE_TYPE_ALL(PREFIX, OP) \
@@ -399,7 +400,7 @@ void Variant::evaluate(const Operator &p_op, const Variant &p_a,
 			CASE_TYPE(math, OP_EQUAL, NIL) {
 				if (p_b.type == NIL) _RETURN(true);
 				if (p_b.type == OBJECT)
-					_RETURN(p_b._get_obj().obj == NULL);
+					_RETURN(_OBJ_PTR(p_b) == NULL);
 
 				_RETURN(false);
 			}
@@ -416,9 +417,9 @@ void Variant::evaluate(const Operator &p_op, const Variant &p_a,
 
 			CASE_TYPE(math, OP_EQUAL, OBJECT) {
 				if (p_b.type == OBJECT)
-					_RETURN((p_a._get_obj().obj == p_b._get_obj().obj));
+					_RETURN(_OBJ_PTR(p_a) == _OBJ_PTR(p_b));
 				if (p_b.type == NIL)
-					_RETURN(p_a._get_obj().obj == NULL);
+					_RETURN(_OBJ_PTR(p_a) == NULL);
 
 				_RETURN_FAIL;
 			}
@@ -486,7 +487,7 @@ void Variant::evaluate(const Operator &p_op, const Variant &p_a,
 			CASE_TYPE(math, OP_NOT_EQUAL, NIL) {
 				if (p_b.type == NIL) _RETURN(false);
 				if (p_b.type == OBJECT)
-					_RETURN(p_b._get_obj().obj != NULL);
+					_RETURN(_OBJ_PTR(p_b) != NULL);
 
 				_RETURN(true);
 			}
@@ -504,9 +505,9 @@ void Variant::evaluate(const Operator &p_op, const Variant &p_a,
 
 			CASE_TYPE(math, OP_NOT_EQUAL, OBJECT) {
 				if (p_b.type == OBJECT)
-					_RETURN((p_a._get_obj().obj != p_b._get_obj().obj));
+					_RETURN((_OBJ_PTR(p_a) != _OBJ_PTR(p_b)));
 				if (p_b.type == NIL)
-					_RETURN(p_a._get_obj().obj != NULL);
+					_RETURN(_OBJ_PTR(p_a) != NULL);
 
 				_RETURN_FAIL;
 			}
@@ -589,7 +590,7 @@ void Variant::evaluate(const Operator &p_op, const Variant &p_a,
 			CASE_TYPE(math, OP_LESS, OBJECT) {
 				if (p_b.type != OBJECT)
 					_RETURN_FAIL;
-				_RETURN((p_a._get_obj().obj < p_b._get_obj().obj));
+				_RETURN(_OBJ_PTR(p_a) < _OBJ_PTR(p_b));
 			}
 
 			CASE_TYPE(math, OP_LESS, ARRAY) {
@@ -643,7 +644,7 @@ void Variant::evaluate(const Operator &p_op, const Variant &p_a,
 			CASE_TYPE(math, OP_LESS_EQUAL, OBJECT) {
 				if (p_b.type != OBJECT)
 					_RETURN_FAIL;
-				_RETURN((p_a._get_obj().obj <= p_b._get_obj().obj));
+				_RETURN(_OBJ_PTR(p_a) <= _OBJ_PTR(p_b));
 			}
 
 			DEFAULT_OP_NUM(math, OP_LESS_EQUAL, INT, <=, _int);
@@ -693,7 +694,7 @@ void Variant::evaluate(const Operator &p_op, const Variant &p_a,
 			CASE_TYPE(math, OP_GREATER, OBJECT) {
 				if (p_b.type != OBJECT)
 					_RETURN_FAIL;
-				_RETURN((p_a._get_obj().obj > p_b._get_obj().obj));
+				_RETURN(_OBJ_PTR(p_a) > _OBJ_PTR(p_b));
 			}
 
 			CASE_TYPE(math, OP_GREATER, ARRAY) {
@@ -747,7 +748,7 @@ void Variant::evaluate(const Operator &p_op, const Variant &p_a,
 			CASE_TYPE(math, OP_GREATER_EQUAL, OBJECT) {
 				if (p_b.type != OBJECT)
 					_RETURN_FAIL;
-				_RETURN((p_a._get_obj().obj >= p_b._get_obj().obj));
+				_RETURN(_OBJ_PTR(p_a) >= _OBJ_PTR(p_b));
 			}
 
 			DEFAULT_OP_NUM(math, OP_GREATER_EQUAL, INT, >=, _int);
@@ -1512,15 +1513,16 @@ void Variant::set_named(const StringName &p_index, const Variant &p_value, bool
 		} break;
 		case OBJECT: {
 
+			Object *obj = _OBJ_PTR(*this);
 #ifdef DEBUG_ENABLED
-			if (!_get_obj().obj) {
-				break;
-			} else if (ScriptDebugger::get_singleton() && _get_obj().ref.is_null() && !ObjectDB::instance_validate(_get_obj().obj)) {
+			if (unlikely(!obj)) {
+				if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+					WARN_PRINT("Attempted set on a deleted object.");
+				}
 				break;
 			}
-
 #endif
-			_get_obj().obj->set(p_index, p_value, &valid);
+			obj->set(p_index, p_value, &valid);
 
 		} break;
 		default: {
@@ -1677,23 +1679,19 @@ Variant Variant::get_named(const StringName &p_index, bool *r_valid) const {
 		} break;
 		case OBJECT: {
 
+			Object *obj = _OBJ_PTR(*this);
 #ifdef DEBUG_ENABLED
-			if (!_get_obj().obj) {
+			if (unlikely(!obj)) {
 				if (r_valid)
 					*r_valid = false;
-				return "Instance base is null.";
-			} else {
-
-				if (ScriptDebugger::get_singleton() && _get_obj().ref.is_null() && !ObjectDB::instance_validate(_get_obj().obj)) {
-					if (r_valid)
-						*r_valid = false;
-					return "Attempted use of stray pointer object.";
+				if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+					WARN_PRINT("Attempted get on a deleted object.");
 				}
+				return Variant();
 			}
-
 #endif
 
-			return _get_obj().obj->get(p_index, r_valid);
+			return obj->get(p_index, r_valid);
 
 		} break;
 		default: {
@@ -2167,29 +2165,24 @@ void Variant::set(const Variant &p_index, const Variant &p_value, bool *r_valid)
 		} break;
 		case OBJECT: {
 
-			Object *obj = _get_obj().obj;
-			//only if debugging!
-
-			if (obj) {
+			Object *obj = _OBJ_PTR(*this);
+			if (unlikely(!obj)) {
 #ifdef DEBUG_ENABLED
-				if (ScriptDebugger::get_singleton() && _get_obj().ref.is_null()) {
-
-					if (!ObjectDB::instance_validate(obj)) {
-						WARN_PRINT("Attempted use of stray pointer object.");
-						valid = false;
-						return;
-					}
+				valid = false;
+				if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+					WARN_PRINT("Attempted set on a deleted object.");
 				}
 #endif
+				return;
+			}
 
-				if (p_index.get_type() != Variant::STRING) {
-					obj->setvar(p_index, p_value, r_valid);
-					return;
-				}
-
-				obj->set(p_index, p_value, r_valid);
+			if (p_index.get_type() != Variant::STRING) {
+				obj->setvar(p_index, p_value, r_valid);
 				return;
 			}
+
+			obj->set(p_index, p_value, r_valid);
+			return;
 		} break;
 		case DICTIONARY: {
 
@@ -2542,23 +2535,20 @@ Variant Variant::get(const Variant &p_index, bool *r_valid) const {
 		case _RID: {
 		} break;
 		case OBJECT: {
-			Object *obj = _get_obj().obj;
-			if (obj) {
-
+			Object *obj = _OBJ_PTR(*this);
+			if (unlikely(!obj)) {
 #ifdef DEBUG_ENABLED
-				if (ScriptDebugger::get_singleton() && _get_obj().ref.is_null()) {
-					//only if debugging!
-					if (!ObjectDB::instance_validate(obj)) {
-						valid = false;
-						return "Attempted get on stray pointer.";
-					}
+				valid = false;
+				if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+					WARN_PRINT("Attempted get on a deleted object.");
 				}
 #endif
+				return Variant();
+			}
 
-				if (p_index.get_type() != Variant::STRING) {
-					return obj->getvar(p_index, r_valid);
-				}
-
+			if (p_index.get_type() != Variant::STRING) {
+				return obj->getvar(p_index, r_valid);
+			} else {
 				return obj->get(p_index, r_valid);
 			}
 
@@ -2606,34 +2596,26 @@ bool Variant::in(const Variant &p_index, bool *r_valid) const {
 
 		} break;
 		case OBJECT: {
-			Object *obj = _get_obj().obj;
-			if (obj) {
-
-				bool valid = false;
+			Object *obj = _OBJ_PTR(*this);
+			if (unlikely(!obj)) {
 #ifdef DEBUG_ENABLED
-				if (ScriptDebugger::get_singleton() && _get_obj().ref.is_null()) {
-					//only if debugging!
-					if (!ObjectDB::instance_validate(obj)) {
-						if (r_valid) {
-							*r_valid = false;
-						}
-						return true; // Attempted get on stray pointer.
-					}
+				if (r_valid) {
+					*r_valid = false;
 				}
-#endif
-
-				if (p_index.get_type() != Variant::STRING) {
-					obj->getvar(p_index, &valid);
-				} else {
-					obj->get(p_index, &valid);
+				if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+					WARN_PRINT("Attempted 'in' on a deleted object.");
 				}
+#endif
+				return false;
+			}
 
-				return valid;
+			bool result;
+			if (p_index.get_type() != Variant::STRING) {
+				obj->getvar(p_index, &result);
 			} else {
-				if (r_valid)
-					*r_valid = false;
+				obj->get(p_index, &result);
 			}
-			return false;
+			return result;
 		} break;
 		case DICTIONARY: {
 
@@ -2880,21 +2862,17 @@ void Variant::get_property_list(List<PropertyInfo> *p_list) const {
 		} break;
 		case OBJECT: {
 
-			Object *obj = _get_obj().obj;
-			if (obj) {
+			Object *obj = _OBJ_PTR(*this);
+			if (unlikely(!obj)) {
 #ifdef DEBUG_ENABLED
-				if (ScriptDebugger::get_singleton() && _get_obj().ref.is_null()) {
-					//only if debugging!
-					if (!ObjectDB::instance_validate(obj)) {
-						WARN_PRINT("Attempted get_property list on stray pointer.");
-						return;
-					}
+				if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+					WARN_PRINT("Attempted get property list on a deleted object.");
 				}
 #endif
-
-				obj->get_property_list(p_list);
+				return;
 			}
 
+			obj->get_property_list(p_list);
 		} break;
 		case DICTIONARY: {
 
@@ -2961,14 +2939,13 @@ bool Variant::iter_init(Variant &r_iter, bool &valid) const {
 		} break;
 		case OBJECT: {
 
+			Object *obj = _OBJ_PTR(*this);
 #ifdef DEBUG_ENABLED
-			if (!_get_obj().obj) {
-				valid = false;
-				return false;
-			}
-
-			if (ScriptDebugger::get_singleton() && _get_obj().ref.is_null() && !ObjectDB::instance_validate(_get_obj().obj)) {
+			if (unlikely(!obj)) {
 				valid = false;
+				if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+					WARN_PRINT("Attempted iteration start on a deleted object.");
+				}
 				return false;
 			}
 #endif
@@ -2978,7 +2955,7 @@ bool Variant::iter_init(Variant &r_iter, bool &valid) const {
 			ref.push_back(r_iter);
 			Variant vref = ref;
 			const Variant *refp[] = { &vref };
-			Variant ret = _get_obj().obj->call(CoreStringNames::get_singleton()->_iter_init, refp, 1, ce);
+			Variant ret = obj->call(CoreStringNames::get_singleton()->_iter_init, refp, 1, ce);
 
 			if (ref.size() != 1 || ce.error != Variant::CallError::CALL_OK) {
 				valid = false;
@@ -3129,14 +3106,13 @@ bool Variant::iter_next(Variant &r_iter, bool &valid) const {
 		} break;
 		case OBJECT: {
 
+			Object *obj = _OBJ_PTR(*this);
 #ifdef DEBUG_ENABLED
-			if (!_get_obj().obj) {
-				valid = false;
-				return false;
-			}
-
-			if (ScriptDebugger::get_singleton() && _get_obj().ref.is_null() && !ObjectDB::instance_validate(_get_obj().obj)) {
+			if (unlikely(!obj)) {
 				valid = false;
+				if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+					WARN_PRINT("Attempted iteration check next on a deleted object.");
+				}
 				return false;
 			}
 #endif
@@ -3146,7 +3122,7 @@ bool Variant::iter_next(Variant &r_iter, bool &valid) const {
 			ref.push_back(r_iter);
 			Variant vref = ref;
 			const Variant *refp[] = { &vref };
-			Variant ret = _get_obj().obj->call(CoreStringNames::get_singleton()->_iter_next, refp, 1, ce);
+			Variant ret = obj->call(CoreStringNames::get_singleton()->_iter_next, refp, 1, ce);
 
 			if (ref.size() != 1 || ce.error != Variant::CallError::CALL_OK) {
 				valid = false;
@@ -3288,21 +3264,20 @@ Variant Variant::iter_get(const Variant &r_iter, bool &r_valid) const {
 		} break;
 		case OBJECT: {
 
+			Object *obj = _OBJ_PTR(*this);
 #ifdef DEBUG_ENABLED
-			if (!_get_obj().obj) {
-				r_valid = false;
-				return Variant();
-			}
-
-			if (ScriptDebugger::get_singleton() && _get_obj().ref.is_null() && !ObjectDB::instance_validate(_get_obj().obj)) {
+			if (unlikely(!obj)) {
 				r_valid = false;
+				if (ScriptDebugger::get_singleton() && _get_obj().instance_id != 0 && !ObjectDB::get_instance(_get_obj().instance_id)) {
+					WARN_PRINT("Attempted iteration get next on a deleted object.");
+				}
 				return Variant();
 			}
 #endif
 			Variant::CallError ce;
 			ce.error = Variant::CallError::CALL_OK;
 			const Variant *refp[] = { &r_iter };
-			Variant ret = _get_obj().obj->call(CoreStringNames::get_singleton()->_iter_get, refp, 1, ce);
+			Variant ret = obj->call(CoreStringNames::get_singleton()->_iter_get, refp, 1, ce);
 
 			if (ce.error != Variant::CallError::CALL_OK) {
 				r_valid = false;