text: #ifndef OBJECTRC_H
  #define OBJECTRC_H
  /*************************************************************************/
  /*  object_rc.h                                                          */
  /*************************************************************************/
  /*                       This file is part of:                           */
  /*                           GODOT ENGINE                                */
  /*                      https://godotengine.org                          */
  /*************************************************************************/
  /* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur.                 */
  /* Copyright (c) 2014-2022 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.                */
  /*************************************************************************/
  
  #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:
  	// This is for allowing debug builds 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.
  	const ObjectID instance_id;
  
  	_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) :
  			instance_id(p_object->get_instance_id()) {
  		// 1 (the Object) + 1 (the first user)
  		_users.store(2, std::memory_order_relaxed);
  		_ptr.store(p_object, std::memory_order_release);
  	}
  };
  
  #endif
  