[MIRROR] EVEN MORE HARDDEL FIXES (#7017)

* EVEN MORE HARDDEL FIXES (#60228)

Fixes a ton of harddels, sourced from #59996
I think this brings us down to like, ~100 per round from ~200, with only like 20 of those being proper hell failures. I've seen harddel profiles below 1 second of total cost. Feeling good.

See you on the other side

Makes the cryopod control computer into a weakref, never trust bee code
Converts brig door timer internal lists to weakrefs
Fixes a harddel caused by qdeling a motion sensitive camera after it had left its source area, jesus christ why didn't we do this already holy shit
Converts the radio implant ref held by the antenna mutation to weakrefs because it isn't reliably cleaned up, makes the radio implant actually qdel its fucking radio
Removes the target var from the throwing datum, it does literally nothing and just exists to cause harddels, mostly for the singularity
 Fixes a cable harddel sourced from things that try to enter blueprints after smoothing, but before roundstart. IE, shuttles. Removes shuttles from the blueprints
Fixes emmisive blockers being added post qdel
Removes some manual ghosting from cryopods, I initially did this for harddel reasons, but I figured out a better fix for that. I'm now doing it because it's got this really strange logic for like "re-entering the game" that doesn't actually link to what the ghostize proc does. We should remove this at some point
Fixes robot hud objects harddeling due to hanging refs
Fixes buildmode related hanging refs, I'm coming for you admin team
Fixes a few instances of trying to add the forensics component post qdel, hhhhhhhhhhh
Fixes some split personality harddels/weirdness
Replaces a use of disconnect_duct with an init qdel hint, I suspect there's more issues with duct harddels, I've seen some odd logs about ahhh the area_contents list, but we can worry about that later
Makes teleporter targets into weakrefs, properly types them as /atom
Makes frequency devices into weakrefs
Makes cameras remove themselves from camera nets on Destroy
Makes tgui ui datums implement destroy, this means if I ever see one hang a ref to user or whatever, I know there's an error with calling close() properly. I've seen this harddel once, but not after this change so I assume there was some error with close(). IDK maybe this is a papering over? Would have to ask @ stylemistake
I've seen logs of beartraps being in world post del, putting a return there just in case. The same is true of nerf darts, but I haven't really looked into that yet
Makes a shoe's ref to untying alerts a weakref, yes this is needed.
Moves clearing client_in_contents to the Login of the new mob. This prevents doing things like ghosting someone before a mob qdel causing harddels
Fixes a harddel set sourced from adding a status effect to a qdeleted thing. Is this an error? I'm honestly not sure.
Converts bsa code to weakrefs
Converts the partner var of heat exchangers to weakrefs
Converts camera assemblies to weakrefs
Fixes some dumb behavior with ammo casings and assuming you'll be on a turf post Destroy parent call
Fixes? merger related harddels, you were never cleared from your own members list, so origin objects would end up making a new list, creating harddels. Potential input from @ ninjanomnom about the logic
Chasms store a static list of "falling atoms", which only exists for chasms that go somewhere else. This list wasn't being cleared of qdeleted objects, which is what happens when you fall in most chasms. Fixes this, and converts the list to weakrefs.
Fixes some runtimes in both sheet code, and the weather listener element. This is here because runtime spam made testing more of a pain, didn't think it needed its own pr
Fixes colorful reagent harddels sourced from reagents that were qdel'd before roundstart. I'm only like 50% sure this actually got it, but the issue may have been solved by #60174, so eh
Turns the nuke op antag datum's ref to the war button into a weakref
Fixes some holopad code that was not nulling refs all the time
Converts camera bugs to weakrefs, this was the result of the bug being "reworked" like 6 years back without taking the existing ref clearing into account. Whole item needs a redo, but this'll do for now.
Ensures that the both pulling and pullee refs are cleared on Destroy
The crew monitor held all users in a non clearing list, makes that list a weakref because I hate everything

Oh and I removed all sources of gas_mixture qdeletion, I'm kinda unsure on this since it's not technically supported, but any harddels from it might? indicate something going wrong with like, gas passing logic. I'd like @ MrStonedOne's thoughts, since I trust him to call me an idiot if I'm wrong.

<!-- Please add a short description of why you think these changes would benefit the game. If you can't justify it in words, it might not be worth adding. -->

## Why it's not good for the game

I crashed sybil like 10 times to get this data, I'm gonna put it to good use. Don't think you're safe sybilites, I'm coming for you.

* EVEN MORE HARDDEL FIXES

Co-authored-by: LemonInTheDark <58055496+LemonInTheDark@users.noreply.github.com>

code/_onclick/hud/robot.dm

@@ -300,6 +300,11 @@
 	icon_state = "[base_icon_state]_[robot?.lamp_enabled ? "on" : "off"]"
 	return ..()
 
+/atom/movable/screen/robot/lamp/Destroy()
+	robot.lampButton = null
+	robot = null
+	return ..()
+
 /atom/movable/screen/robot/modPC
 	name = "Modular Interface"
 	icon_state = "template"
@@ -311,6 +316,11 @@
 		return
 	robot.modularInterface?.interact(robot)
 
+/atom/movable/screen/robot/modPC/Destroy()
+	robot.interfaceButton = null
+	robot = null
+	return ..()
+
 /atom/movable/screen/robot/alerts
 	name = "Alert Panel"
 	icon = 'icons/hud/screen_ai.dmi'

code/_onclick/observer.dm

@@ -76,6 +76,12 @@
 	return ..()
 
 /obj/machinery/teleport/hub/attack_ghost(mob/user)
-	if(power_station?.engaged && power_station.teleporter_console && power_station.teleporter_console.target)
-		user.abstract_move(get_turf(power_station.teleporter_console.target))
-	return ..()
+	if(!power_station?.engaged || !power_station.teleporter_console || !power_station.teleporter_console.target_ref)
+		return ..()
+
+	var/atom/target = power_station.teleporter_console.target_ref.resolve()
+	if(!target)
+		power_station.teleporter_console.target_ref = null
+		return ..()
+
+	user.abstract_move(get_turf(target))

code/controllers/subsystem/icon_smooth.dm

@@ -47,7 +47,7 @@ SUBSYSTEM_DEF(icon_smooth)
 		CHECK_TICK
 
 	queue = blueprint_queue
-	blueprint_queue = list()
+	blueprint_queue = null
 
 	for(var/item in queue)
 		var/atom/movable/movable_item = item
@@ -70,5 +70,6 @@ SUBSYSTEM_DEF(icon_smooth)
 /datum/controller/subsystem/icon_smooth/proc/remove_from_queues(atom/thing)
 	thing.smoothing_flags &= ~SMOOTH_QUEUED
 	smooth_queue -= thing
-	blueprint_queue -= thing
+	if(blueprint_queue)
+		blueprint_queue -= thing
 	deferred -= thing

code/controllers/subsystem/throwing.dm

@@ -42,7 +42,6 @@ SUBSYSTEM_DEF(throwing)
 
 /datum/thrownthing
 	var/atom/movable/thrownthing
-	var/atom/target
 	var/turf/target_turf
 	var/target_zone
 	var/init_dir
@@ -66,11 +65,10 @@ SUBSYSTEM_DEF(throwing)
 	var/last_move = 0
 
 
-/datum/thrownthing/New(thrownthing, target, target_turf, init_dir, maxrange, speed, thrower, diagonals_first, force, gentle, callback, target_zone)
+/datum/thrownthing/New(thrownthing, target_turf, init_dir, maxrange, speed, thrower, diagonals_first, force, gentle, callback, target_zone)
 	. = ..()
 	src.thrownthing = thrownthing
 	RegisterSignal(thrownthing, COMSIG_PARENT_QDELETING, .proc/on_thrownthing_qdel)
-	src.target = target
 	src.target_turf = target_turf
 	src.init_dir = init_dir
 	src.maxrange = maxrange
@@ -88,7 +86,6 @@ SUBSYSTEM_DEF(throwing)
 	SSthrowing.currentrun -= thrownthing
 	thrownthing.throwing = null
 	thrownthing = null
-	target = null
 	thrower = null
 	if(callback)
 		QDEL_NULL(callback) //It stores a reference to the thrownthing, its source. Let's clean that.

code/datums/brain_damage/split_personality.dm

@@ -58,6 +58,13 @@
 	QDEL_NULL(owner_backseat)
 	..()
 
+/datum/brain_trauma/severe/split_personality/Destroy()
+	if(stranger_backseat)
+		QDEL_NULL(stranger_backseat)
+	if(owner_backseat)
+		QDEL_NULL(owner_backseat)
+	return ..()
+
 /datum/brain_trauma/severe/split_personality/proc/switch_personalities(reset_to_owner = FALSE)
 	if(QDELETED(owner) || QDELETED(stranger_backseat) || QDELETED(owner_backseat))
 		return

code/datums/components/chasm.dm

@@ -4,7 +4,8 @@
 	var/fall_message = "GAH! Ah... where are you?"
 	var/oblivion_message = "You stumble and stare into the abyss before you. It stares back, and you fall into the enveloping dark."
 
-	var/static/list/falling_atoms = list() // Atoms currently falling into chasms
+	/// List of refs to falling objects -> how many levels deep we've fallen
+	var/static/list/falling_atoms = list()
 	var/static/list/forbidden_types = typecacheof(list(
 		/obj/singularity,
 		/obj/energy_ball,
@@ -54,7 +55,6 @@
 	return LAZYLEN(found_safeties)
 
 /datum/component/chasm/proc/drop_stuff(AM)
-	. = 0
 	if (is_safe())
 		return FALSE
 
@@ -62,12 +62,13 @@
 	var/to_check = AM ? list(AM) : parent.contents
 	for (var/thing in to_check)
 		if (droppable(thing))
-			. = 1
+			. = TRUE
 			INVOKE_ASYNC(src, .proc/drop, thing)
 
 /datum/component/chasm/proc/droppable(atom/movable/AM)
+	var/datum/weakref/falling_ref = WEAKREF(AM)
 	// avoid an infinite loop, but allow falling a large distance
-	if(falling_atoms[AM] && falling_atoms[AM] > 30)
+	if(falling_atoms[falling_ref] && falling_atoms[falling_ref] > 30)
 		return FALSE
 	if(!isliving(AM) && !isobj(AM))
 		return FALSE
@@ -91,10 +92,12 @@
 	return TRUE
 
 /datum/component/chasm/proc/drop(atom/movable/AM)
+	var/datum/weakref/falling_ref = WEAKREF(AM)
 	//Make sure the item is still there after our sleep
-	if(!AM || QDELETED(AM))
+	if(!AM || !falling_ref?.resolve())
+		falling_atoms -= falling_ref
 		return
-	falling_atoms[AM] = (falling_atoms[AM] || 0) + 1
+	falling_atoms[falling_ref] = (falling_atoms[falling_ref] || 0) + 1
 	var/turf/T = target_turf
 
 	if(T)
@@ -106,7 +109,7 @@
 			var/mob/living/L = AM
 			L.Paralyze(100)
 			L.adjustBruteLoss(30)
-		falling_atoms -= AM
+		falling_atoms -= falling_ref
 
 	else
 		// send to oblivion
@@ -135,7 +138,7 @@
 			var/mob/living/silicon/robot/S = AM
 			qdel(S.mmi)
 
-		falling_atoms -= AM
+		falling_atoms -= falling_ref
 		qdel(AM)
 		if(AM && !QDELETED(AM)) //It's indestructible
 			var/atom/parent = src.parent

code/datums/elements/weather_listener.dm

@@ -24,8 +24,8 @@
 		weather_trait = trait
 		playlist = weather_playlist
 
-	RegisterSignal(target, COMSIG_MOVABLE_Z_CHANGED, .proc/handle_z_level_change)
-	RegisterSignal(target, COMSIG_MOB_LOGOUT, .proc/handle_logout)
+	RegisterSignal(target, COMSIG_MOVABLE_Z_CHANGED, .proc/handle_z_level_change, override = TRUE)
+	RegisterSignal(target, COMSIG_MOB_LOGOUT, .proc/handle_logout, override = TRUE)
 
 /datum/element/weather_listener/Detach(datum/source)
 	. = ..()

code/datums/holocall.dm

@@ -81,6 +81,7 @@
 	if(!QDELETED(hologram))
 		hologram.HC = null
 		QDEL_NULL(hologram)
+	hologram = null
 
 	for(var/I in dialed_holopads)
 		var/obj/machinery/holopad/H = I

code/datums/mergers/_merger.dm

@@ -19,10 +19,7 @@
 #endif
 
 	/// Signals in members to trigger a refresh
-	var/static/list/refresh_signals = list(
-		COMSIG_PARENT_QDELETING,
-		COMSIG_MOVABLE_MOVED,
-	)
+	var/static/list/refresh_signals = list(COMSIG_MOVABLE_MOVED)
 
 /datum/merger/New(id, list/merged_typecache, atom/origin, attempt_merge_proc)
 #if MERGERS_DEBUG
@@ -42,18 +39,21 @@
 /datum/merger/proc/RemoveMember(atom/thing, clean=TRUE)
 	SEND_SIGNAL(thing, COMSIG_MERGER_REMOVING, src)
 	UnregisterSignal(thing, refresh_signals)
+	UnregisterSignal(thing, COMSIG_PARENT_QDELETING)
 	if(!thing.mergers)
 		return
 	thing.mergers -= id
 	if(clean && !length(thing.mergers))
 		thing.mergers = null
 	members -= thing
+	origin = null
 	if(origin == thing && length(members))
 		origin = pick(members)
 
 /datum/merger/proc/AddMember(atom/thing, connected_dir) // note that this fires for the origin of the merger as well
 	SEND_SIGNAL(thing, COMSIG_MERGER_ADDING, src)
 	RegisterSignal(thing, refresh_signals, .proc/QueueRefresh)
+	RegisterSignal(thing, COMSIG_PARENT_QDELETING, .proc/HandleMemberDel)
 	if(!thing.mergers)
 		thing.mergers = list()
 	else if(thing.mergers[id])
@@ -73,6 +73,11 @@
 		sleep(1 SECONDS)
 #endif
 
+/datum/merger/proc/HandleMemberDel(atom/source)
+	SIGNAL_HANDLER
+	RemoveMember(source)
+	QueueRefresh()
+
 /datum/merger/proc/QueueRefresh()
 	SIGNAL_HANDLER
 	addtimer(CALLBACK(src, .proc/Refresh), 1, TIMER_UNIQUE)

code/datums/mutations/antenna.dm

@@ -6,7 +6,7 @@
 	text_lose_indication = "<span class='notice'>Your antenna shrinks back down.</span>"
 	instability = 5
 	difficulty = 8
-	var/obj/item/implant/radio/antenna/linked_radio
+	var/datum/weakref/radio_weakref
 
 /obj/item/implant/radio/antenna
 	name = "internal antenna organ"
@@ -21,13 +21,16 @@
 /datum/mutation/human/antenna/on_acquiring(mob/living/carbon/human/owner)
 	if(..())
 		return
-	linked_radio = new(owner)
+	var/obj/item/implant/radio/antenna/linked_radio = new(owner)
 	linked_radio.implant(owner, null, TRUE, TRUE)
+	radio_weakref = WEAKREF(linked_radio)
 
 /datum/mutation/human/antenna/on_losing(mob/living/carbon/human/owner)
 	if(..())
 		return
-	QDEL_NULL(linked_radio)
+	var/obj/item/implant/radio/antenna/linked_radio = radio_weakref.resolve()
+	if(linked_radio)
+		QDEL_NULL(linked_radio)
 
 /datum/mutation/human/antenna/New(class_ = MUT_OTHER, timer, datum/mutation/human/copymut)
 	..()

code/datums/status_effects/status_effect.dm

@@ -21,11 +21,11 @@
 /datum/status_effect/proc/on_creation(mob/living/new_owner, ...)
 	if(new_owner)
 		owner = new_owner
-	if(owner)
-		LAZYADD(owner.status_effects, src)
-	if(!owner || !on_apply())
+	if(QDELETED(owner) || !on_apply())
 		qdel(src)
 		return
+	if(owner)
+		LAZYADD(owner.status_effects, src)
 	if(duration != -1)
 		duration = world.time + duration
 	tick_interval = world.time + tick_interval

code/game/atoms.dm

@@ -455,7 +455,6 @@
 
 ///Take air from the passed in gas mixture datum
 /atom/proc/assume_air(datum/gas_mixture/giver)
-	qdel(giver)
 	return null
 
 ///Remove air from this atom

code/game/atoms_movable.dm

@@ -129,6 +129,8 @@
 
 	if(pulledby)
 		pulledby.stop_pulling()
+	if(pulling)
+		stop_pulling()
 
 	if(orbiting)
 		orbiting.end_orbit(src)
@@ -159,7 +161,7 @@
 		gen_emissive_blocker.appearance_flags |= appearance_flags
 		return gen_emissive_blocker
 	else if(blocks_emissive == EMISSIVE_BLOCK_UNIQUE)
-		if(!em_block)
+		if(!em_block && !QDELETED(src))
 			render_target = ref(src)
 			em_block = new(src, render_target)
 		return em_block
@@ -872,7 +874,7 @@
 	else
 		target_zone = thrower.zone_selected
 
-	var/datum/thrownthing/TT = new(src, target, get_turf(target), get_dir(src, target), range, speed, thrower, diagonals_first, force, gentle, callback, target_zone)
+	var/datum/thrownthing/TT = new(src, get_turf(target), get_dir(src, target), range, speed, thrower, diagonals_first, force, gentle, callback, target_zone)
 
 	var/dist_x = abs(target.x - src.x)
 	var/dist_y = abs(target.y - src.y)

code/game/communications.dm

@@ -134,8 +134,9 @@ GLOBAL_LIST_INIT(reverseradiochannels, list(
 ))
 
 /datum/radio_frequency
-	var/frequency as num
-	var/list/list/obj/devices = list()
+	var/frequency
+	/// List of filters -> list of devices
+	var/list/list/datum/weakref/devices = list()
 
 /datum/radio_frequency/New(freq)
 	frequency = freq
@@ -165,7 +166,11 @@ GLOBAL_LIST_INIT(reverseradiochannels, list(
 
 	//Send the data
 	for(var/current_filter in filter_list)
-		for(var/obj/device in devices[current_filter])
+		for(var/datum/weakref/device_ref as anything in devices[current_filter])
+			var/obj/device = device_ref.resolve()
+			if(!device)
+				devices[current_filter] -= device_ref
+				continue
 			if(device == source)
 				continue
 			if(range)
@@ -183,7 +188,7 @@ GLOBAL_LIST_INIT(reverseradiochannels, list(
 	var/list/devices_line = devices[filter]
 	if(!devices_line)
 		devices[filter] = devices_line = list()
-	devices_line += device
+	devices_line += WEAKREF(device)
 
 
 /datum/radio_frequency/proc/remove_listener(obj/device)
@@ -191,7 +196,7 @@ GLOBAL_LIST_INIT(reverseradiochannels, list(
 		var/list/devices_line = devices[devices_filter]
 		if(!devices_line)
 			devices -= devices_filter
-		devices_line -= device
+		devices_line -= WEAKREF(device)
 		if(!devices_line.len)
 			devices -= devices_filter
 

code/game/machinery/camera/camera.dm

@@ -23,7 +23,7 @@
 	var/start_active = FALSE //If it ignores the random chance to start broken on round start
 	var/invuln = null
 	var/obj/item/camera_bug/bug = null
-	var/obj/structure/camera_assembly/assembly = null
+	var/datum/weakref/assembly_ref = null
 	var/area/myarea = null
 
 	//OTHER
@@ -56,6 +56,7 @@
 	for(var/i in network)
 		network -= i
 		network += lowertext(i)
+	var/obj/structure/camera_assembly/assembly
 	if(CA)
 		assembly = CA
 		if(assembly.xray_module)
@@ -73,6 +74,7 @@
 	else
 		assembly = new(src)
 		assembly.state = 4 //STATE_FINISHED
+	assembly_ref = WEAKREF(assembly)
 	GLOB.cameranet.cameras += src
 	GLOB.cameranet.addCamera(src)
 	if (isturf(loc))
@@ -100,11 +102,12 @@
 /obj/machinery/camera/Destroy()
 	if(can_use())
 		toggle_cam(null, 0) //kick anyone viewing out and remove from the camera chunks
+	GLOB.cameranet.removeCamera(src)
 	GLOB.cameranet.cameras -= src
 	cancelCameraAlarm()
 	if(isarea(myarea))
 		myarea.clear_camera(src)
-	QDEL_NULL(assembly)
+	QDEL_NULL(assembly_ref)
 	if(bug)
 		bug.bugged_cameras -= c_tag
 		if(bug.current == src)
@@ -204,6 +207,10 @@
 	. = ..()
 	if(!panel_open)
 		return
+	var/obj/structure/camera_assembly/assembly = assembly_ref?.resolve()
+	if(!assembly)
+		assembly_ref = null
+		return
 	var/list/droppable_parts = list()
 	if(assembly.xray_module)
 		droppable_parts += assembly.xray_module
@@ -267,6 +274,9 @@
 /obj/machinery/camera/attackby(obj/item/I, mob/living/user, params)
 	// UPGRADES
 	if(panel_open)
+		var/obj/structure/camera_assembly/assembly = assembly_ref?.resolve()
+		if(!assembly)
+			assembly_ref = null
 		if(I.tool_behaviour == TOOL_ANALYZER)
 			if(!isXRay(TRUE)) //don't reveal it was already upgraded if was done via MALF AI Upgrade Camera Network ability
 				if(!user.temporarilyRemoveItemFromInventory(I))
@@ -342,7 +352,7 @@
 		else
 			to_chat(user, span_notice("Camera bugged."))
 			bug = I
-			bug.bugged_cameras[src.c_tag] = src
+			bug.bugged_cameras[src.c_tag] = WEAKREF(src)
 		return
 
 	return ..()
@@ -364,12 +374,13 @@
 /obj/machinery/camera/deconstruct(disassembled = TRUE)
 	if(!(flags_1 & NODECONSTRUCT_1))
 		if(disassembled)
+			var/obj/structure/camera_assembly/assembly = assembly_ref?.resolve()
 			if(!assembly)
 				assembly = new()
 			assembly.forceMove(drop_location())
 			assembly.state = 1
 			assembly.setDir(dir)
-			assembly = null
+			assembly_ref = null
 		else
 			var/obj/item/I = new /obj/item/wallframe/camera (loc)
 			I.update_integrity(I.max_integrity * 0.5)

code/game/machinery/camera/motion.dm

@@ -38,10 +38,9 @@
 	return TRUE
 
 /obj/machinery/camera/Destroy()
-	var/area/ai_monitored/A = get_area(src)
 	localMotionTargets = null
-	if(istype(A))
-		A.motioncameras -= src
+	if(area_motion)
+		area_motion.motioncameras -= src
 	cancelAlarm()
 	return ..()
 

code/game/machinery/camera/presets.dm

@@ -72,12 +72,14 @@
 // UPGRADE PROCS
 
 /obj/machinery/camera/proc/isEmpProof(ignore_malf_upgrades)
-	return (upgrades & CAMERA_UPGRADE_EMP_PROOF) && (!(ignore_malf_upgrades && assembly.malf_emp_firmware_active))
+	var/obj/structure/camera_assembly/assembly = assembly_ref?.resolve()
+	return (upgrades & CAMERA_UPGRADE_EMP_PROOF) && (!(ignore_malf_upgrades && assembly?.malf_emp_firmware_active))
 
 /obj/machinery/camera/proc/upgradeEmpProof(malf_upgrade, ignore_malf_upgrades)
 	if(isEmpProof(ignore_malf_upgrades)) //pass a malf upgrade to ignore_malf_upgrades so we can replace the malf module with the normal one
 		return //that way if someone tries to upgrade an already malf-upgraded camera, it'll just upgrade it to a normal version.
 	AddElement(/datum/element/empprotection, EMP_PROTECT_SELF | EMP_PROTECT_WIRES | EMP_PROTECT_CONTENTS)
+	var/obj/structure/camera_assembly/assembly = assembly_ref?.resolve()
 	if(malf_upgrade)
 		assembly.malf_emp_firmware_active = TRUE //don't add parts to drop, update icon, ect. reconstructing it will also retain the upgrade.
 		assembly.malf_emp_firmware_present = TRUE //so the upgrade is retained after incompatible parts are removed.
@@ -98,11 +100,13 @@
 
 
 /obj/machinery/camera/proc/isXRay(ignore_malf_upgrades)
+	var/obj/structure/camera_assembly/assembly = assembly_ref?.resolve()
 	return (upgrades & CAMERA_UPGRADE_XRAY) && (!(ignore_malf_upgrades && assembly.malf_xray_firmware_active))
 
 /obj/machinery/camera/proc/upgradeXRay(malf_upgrade, ignore_malf_upgrades)
 	if(isXRay(ignore_malf_upgrades)) //pass a malf upgrade to ignore_malf_upgrades so we can replace the malf upgrade with the normal one
 		return //that way if someone tries to upgrade an already malf-upgraded camera, it'll just upgrade it to a normal version.
+	var/obj/structure/camera_assembly/assembly = assembly_ref?.resolve()
 	if(malf_upgrade)
 		assembly.malf_xray_firmware_active = TRUE //don't add parts to drop, update icon, ect. reconstructing it will also retain the upgrade.
 		assembly.malf_xray_firmware_present = TRUE //so the upgrade is retained after incompatible parts are removed.
@@ -128,6 +132,8 @@
 /obj/machinery/camera/proc/upgradeMotion()
 	if(isMotion())
 		return
+	var/obj/structure/camera_assembly/assembly = assembly_ref?.resolve()
+
 	if(name == initial(name))
 		name = "motion-sensitive security camera"
 	if(!assembly.proxy_module)

code/game/machinery/computer/atmos_control.dm

@@ -417,7 +417,16 @@ GLOBAL_LIST_EMPTY(atmos_air_controllers)
 /obj/machinery/computer/atmos_control/tank/proc/reconnect(mob/user)
 	var/list/IO = list()
 	var/datum/radio_frequency/freq = SSradio.return_frequency(frequency)
-	var/list/devices = freq.devices["_default"]
+
+	var/list/devices = list()
+	var/list/device_refs = freq.devices["_default"]
+	for(var/datum/weakref/device_ref as anything in device_refs)
+		var/atom/device = device_ref.resolve()
+		if(!device)
+			device_refs -= device_ref
+			continue
+		devices += device
+
 	for(var/obj/machinery/atmospherics/components/unary/vent_pump/U in devices)
 		var/list/text = splittext(U.id_tag, "_")
 		IO |= text[1]

code/game/machinery/computer/crew.dm

@@ -172,11 +172,11 @@ GLOBAL_DATUM_INIT(crewmonitor, /datum/crewmonitor, new)
 		ui.open()
 
 /datum/crewmonitor/proc/show(mob/M, source)
-	ui_sources[M] = source
+	ui_sources[WEAKREF(M)] = source
 	ui_interact(M)
 
 /datum/crewmonitor/ui_host(mob/user)
-	return ui_sources[user]
+	return ui_sources[WEAKREF(user)]
 
 /datum/crewmonitor/ui_data(mob/user)
 	var/z = user.z

code/game/machinery/computer/teleporter.dm

@@ -10,7 +10,8 @@
 	var/id
 	var/obj/machinery/teleport/station/power_station
 	var/calibrating
-	var/turf/target
+	///Weakref to the target atom we're pointed at currently
+	var/datum/weakref/target_ref
 
 /obj/machinery/computer/teleporter/Initialize()
 	. = ..()
@@ -45,6 +46,11 @@
 		ui.open()
 
 /obj/machinery/computer/teleporter/ui_data(mob/user)
+	var/atom/target
+	if(target_ref)
+		target = target_ref.resolve()
+	if(!target)
+		target_ref = null
 	var/list/data = list()
 	data["power_station"] = power_station ? TRUE : FALSE
 	data["teleporter_hub"] = power_station?.teleporter_hub ? TRUE : FALSE
@@ -85,7 +91,7 @@
 			set_target(usr)
 			. = TRUE
 		if("calibrate")
-			if(!target)
+			if(!target_ref)
 				say("Error: No target set to calibrate to.")
 				return
 			if(power_station.teleporter_hub.calibrated || power_station.teleporter_hub.accuracy >= 3)
@@ -96,13 +102,14 @@
 			calibrating = TRUE
 			power_station.update_appearance()
 			addtimer(CALLBACK(src, .proc/finish_calibration), 50 * (3 - power_station.teleporter_hub.accuracy)) //Better parts mean faster calibration
-			. = TRUE
+			return TRUE
 
 /obj/machinery/computer/teleporter/proc/set_teleport_target(new_target)
-	if (target == new_target)
+	var/datum/weakref/new_target_ref = WEAKREF(new_target)
+	if (target_ref == new_target_ref)
 		return
 	SEND_SIGNAL(src, COMSIG_TELEPORTER_NEW_TARGET, new_target)
-	target = new_target
+	target_ref = new_target_ref
 
 /obj/machinery/computer/teleporter/proc/finish_calibration()
 	calibrating = FALSE
@@ -152,8 +159,8 @@
 
 		var/desc = input("Please select a location to lock in.", "Locking Computer") as null|anything in sortList(L)
 		set_teleport_target(L[desc])
-		var/turf/T = get_turf(target)
-		log_game("[key_name(user)] has set the teleporter target to [target] at [AREACOORD(T)]")
+		var/turf/T = get_turf(L[desc])
+		log_game("[key_name(user)] has set the teleporter target to [L[desc]] at [AREACOORD(T)]")
 
 	else
 		var/list/S = power_station.linked_stations

code/game/machinery/cryopod.dm

@@ -137,7 +137,8 @@ GLOBAL_LIST_EMPTY(cryopod_computers)
 	/// Cooldown for when it's now safe to try an despawn the player.
 	COOLDOWN_DECLARE(despawn_world_time)
 
-	var/obj/machinery/computer/cryopod/control_computer
+	///Weakref to our controller
+	var/datum/weakref/control_computer_weakref
 	COOLDOWN_DECLARE(last_no_computer_message)
 
 /obj/machinery/cryopod/Initialize()
@@ -150,27 +151,27 @@ GLOBAL_LIST_EMPTY(cryopod_computers)
 
 // This is not a good situation
 /obj/machinery/cryopod/Destroy()
-	control_computer = null
+	control_computer_weakref = null
 	return ..()
 
 /obj/machinery/cryopod/proc/find_control_computer(urgent = FALSE)
 	for(var/cryo_console as anything in GLOB.cryopod_computers)
 		var/obj/machinery/computer/cryopod/console = cryo_console
 		if(get_area(console) == get_area(src))
-			control_computer = console
+			control_computer_weakref = WEAKREF(console)
 			break
 
 	// Don't send messages unless we *need* the computer, and less than five minutes have passed since last time we messaged
-	if(!control_computer && urgent && COOLDOWN_FINISHED(src, last_no_computer_message))
+	if(!control_computer_weakref && urgent && COOLDOWN_FINISHED(src, last_no_computer_message))
 		COOLDOWN_START(src, last_no_computer_message, 5 MINUTES)
 		log_admin("Cryopod in [get_area(src)] could not find control computer!")
 		message_admins("Cryopod in [get_area(src)] could not find control computer!")
 		last_no_computer_message = world.time
 
-	return control_computer != null
+	return control_computer_weakref != null
 
 /obj/machinery/cryopod/close_machine(atom/movable/target)
-	if(!control_computer)
+	if(!control_computer_weakref)
 		find_control_computer(TRUE)
 	if((isnull(target) || isliving(target)) && state_open && !panel_open)
 		..(target)
@@ -204,7 +205,7 @@ GLOBAL_LIST_EMPTY(cryopod_computers)
 		open_machine()
 
 	if(!mob_occupant.client && COOLDOWN_FINISHED(src, despawn_world_time))
-		if(!control_computer)
+		if(!control_computer_weakref)
 			find_control_computer(urgent = TRUE)
 
 		despawn_occupant()
@@ -298,7 +299,11 @@ GLOBAL_LIST_EMPTY(cryopod_computers)
 			announce_rank = general_record.fields["rank"]
 			qdel(general_record)
 
-	control_computer?.frozen_crew += list(crew_member)
+	var/obj/machinery/computer/cryopod/control_computer = control_computer_weakref?.resolve()
+	if(!control_computer)
+		control_computer_weakref = null
+	else
+		control_computer.frozen_crew += list(crew_member)
 
 	// Make an announcement and log the person entering storage.
 	if(GLOB.announcement_systems.len)
@@ -323,13 +328,6 @@ GLOBAL_LIST_EMPTY(cryopod_computers)
 		else mob_occupant.transferItemToLoc(item_content, drop_location(), force = TRUE, silent = TRUE)
 // Skyrat Edit End
 
-	// Ghost and delete the mob.
-	if(!mob_occupant.get_ghost(TRUE))
-		if(world.time < 15 MINUTES) // before the 15 minute mark
-			mob_occupant.ghostize(FALSE) // Players despawned too early may not re-enter the game
-		else
-			mob_occupant.ghostize(TRUE)
-
 	handle_objectives()
 	QDEL_NULL(occupant)
 	open_machine()

code/game/machinery/doors/brigdoors.dm

@@ -32,7 +32,13 @@
 	var/timer_duration = 0
 
 	var/timing = FALSE // boolean, true/1 timer is on, false/0 means it's not timing
-	var/list/obj/machinery/targets = list()
+	///List of weakrefs to nearby doors
+	var/list/doors = list()
+	///List of weakrefs to nearby flashers
+	var/list/flashers = list()
+	///List of weakrefs to nearby closets
+	var/list/closets = list()
+
 	var/obj/item/radio/Radio //needed to send messages to sec radio
 
 	maptext_height = 26
@@ -50,17 +56,17 @@
 	if(id != null)
 		for(var/obj/machinery/door/window/brigdoor/M in urange(20, src))
 			if (M.id == id)
-				targets += M
+				doors += WEAKREF(M)
 
 		for(var/obj/machinery/flasher/F in urange(20, src))
 			if(F.id == id)
-				targets += F
+				flashers += WEAKREF(F)
 
 		for(var/obj/structure/closet/secure_closet/brig/C in urange(20, src))
 			if(C.id == id)
-				targets += C
+				closets += WEAKREF(C)
 
-	if(!targets.len)
+	if(!length(doors) && !length(flashers) && length(closets))
 		obj_break()
 	update_appearance()
 
@@ -88,18 +94,26 @@
 	activation_time = world.realtime //SKYRAT EDIT CHANGE
 	timing = TRUE
 
-	for(var/obj/machinery/door/window/brigdoor/door in targets)
+	for(var/datum/weakref/door_ref as anything in doors)
+		var/obj/machinery/door/window/brigdoor/door = door_ref.resolve()
+		if(!door)
+			doors -= door_ref
+			continue
 		if(door.density)
 			continue
 		INVOKE_ASYNC(door, /obj/machinery/door/window/brigdoor.proc/close)
 
-	for(var/obj/structure/closet/secure_closet/brig/C in targets)
-		if(C.broken)
+	for(var/datum/weakref/closet_ref as anything in closets)
+		var/obj/structure/closet/secure_closet/brig/closet = closet_ref.resolve()
+		if(!closet)
+			closets -= closet_ref
 			continue
-		if(C.opened && !C.close())
+		if(closet.broken)
 			continue
-		C.locked = TRUE
-		C.update_appearance()
+		if(closet.opened && !closet.close())
+			continue
+		closet.locked = TRUE
+		closet.update_appearance()
 	return 1
 
 
@@ -117,18 +131,26 @@
 	set_timer(0)
 	update_appearance()
 
-	for(var/obj/machinery/door/window/brigdoor/door in targets)
+	for(var/datum/weakref/door_ref as anything in doors)
+		var/obj/machinery/door/window/brigdoor/door = door_ref.resolve()
+		if(!door)
+			doors -=  door_ref
+			continue
 		if(!door.density)
 			continue
 		INVOKE_ASYNC(door, /obj/machinery/door/window/brigdoor.proc/open)
 
-	for(var/obj/structure/closet/secure_closet/brig/C in targets)
-		if(C.broken)
+	for(var/datum/weakref/closet_ref as anything in closets)
+		var/obj/structure/closet/secure_closet/brig/closet = closet_ref.resolve()
+		if(!closet)
+			closets -= closet_ref
 			continue
-		if(C.opened)
+		if(closet.broken)
 			continue
-		C.locked = FALSE
-		C.update_appearance()
+		if(closet.opened)
+			continue
+		closet.locked = FALSE
+		closet.update_appearance()
 
 	return 1
 
@@ -200,8 +222,12 @@
 	data["minutes"] = round((time_left - data["seconds"]) / 60)
 	data["timing"] = timing
 	data["flash_charging"] = FALSE
-	for(var/obj/machinery/flasher/F in targets)
-		if(F.last_flash && (F.last_flash + 15 SECONDS) > world.time)
+	for(var/datum/weakref/flash_ref as anything in flashers)
+		var/obj/machinery/flasher/flasher = flash_ref.resolve()
+		if(!flasher)
+			flashers -= flash_ref
+			continue
+		if(flasher.last_flash && (flasher.last_flash + 15 SECONDS) > world.time)
 			data["flash_charging"] = TRUE
 			break
 	return data
@@ -238,8 +264,12 @@
 		if("flash")
 			investigate_log("[key_name(usr)] has flashed cell [id]", INVESTIGATE_RECORDS)
 			user.log_message("[key_name(usr)] has flashed cell [id]", LOG_ATTACK)
-			for(var/obj/machinery/flasher/F in targets)
-				F.flash()
+			for(var/datum/weakref/flash_ref as anything in flashers)
+				var/obj/machinery/flasher/flasher = flash_ref.resolve()
+				if(!flasher)
+					flashers -= flash_ref
+					continue
+				flasher.flash()
 		if("preset")
 			var/preset = params["preset"]
 			var/preset_time = time_left()

code/game/machinery/hologram.dm

@@ -726,6 +726,7 @@ For the other part of the code, check silicon say.dm. Particularly robot talk.*/
 	Impersonation = null
 	if(!QDELETED(HC))
 		HC.Disconnect(HC.calling_holopad)
+	HC = null
 	return ..()
 
 /obj/effect/overlay/holo_pad_hologram/Process_Spacemove(movement_dir = 0)

code/game/machinery/teleporter.dm

@@ -68,12 +68,15 @@
 	var/obj/machinery/computer/teleporter/com = power_station.teleporter_console
 	if (QDELETED(com))
 		return
-	if (QDELETED(com.target))
-		com.target = null
+	var/atom/target
+	if(com.target_ref)
+		target = com.target_ref.resolve()
+	if (!target)
+		com.target_ref = null
 		visible_message(span_alert("Cannot authenticate locked on coordinates. Please reinstate coordinate matrix."))
 		return
 	if (ismovable(M))
-		if(do_teleport(M, com.target, channel = TELEPORT_CHANNEL_BLUESPACE))
+		if(do_teleport(M, target, channel = TELEPORT_CHANNEL_BLUESPACE))
 			use_power(5000)
 			if(!calibrated && prob(30 - ((accuracy) * 10))) //oh dear a problem
 				if(ishuman(M))//don't remove people from the round randomly you jerks
@@ -214,7 +217,7 @@
 /obj/machinery/teleport/station/proc/toggle(mob/user)
 	if(machine_stat & (BROKEN|NOPOWER) || !teleporter_hub || !teleporter_console )
 		return
-	if (teleporter_console.target)
+	if (teleporter_console.target_ref?.resolve())
 		if(teleporter_hub.panel_open || teleporter_hub.machine_stat & (BROKEN|NOPOWER))
 			to_chat(user, span_alert("The teleporter hub isn't responding."))
 		else
@@ -222,6 +225,7 @@
 			use_power(5000)
 			to_chat(user, span_notice("Teleporter [engaged ? "" : "dis"]engaged!"))
 	else
+		teleporter_console.target_ref = null
 		to_chat(user, span_alert("No target detected."))
 		engaged = FALSE
 	teleporter_hub.update_appearance()

code/game/objects/items/devices/camera_bug.dm

@@ -39,7 +39,8 @@
 	STOP_PROCESSING(SSobj, src)
 	get_cameras()
 	for(var/cam_tag in bugged_cameras)
-		var/obj/machinery/camera/camera = bugged_cameras[cam_tag]
+		var/datum/weakref/camera_ref = bugged_cameras[cam_tag]
+		var/obj/machinery/camera/camera = camera_ref.resolve()
 		if(camera && camera.bug == src)
 			camera.bug = null
 	bugged_cameras = list()
@@ -81,8 +82,11 @@
 		for(var/obj/machinery/camera/camera in GLOB.cameranet.cameras)
 			if(camera.machine_stat || !camera.can_use())
 				continue
-			if(length(list("ss13","mine", "rd", "labor", "toxins", "minisat")&camera.network))
-				bugged_cameras[camera.c_tag] = camera
+			if(length(list("ss13","mine", "rd", "labor", "toxins", "minisat") & camera.network))
+				var/datum/weakref/camera_ref = WEAKREF(camera)
+				if(!camera_ref || !camera.c_tag)
+					continue
+				bugged_cameras[camera.c_tag] = camera_ref
 	return sortList(bugged_cameras)
 
 
@@ -95,15 +99,17 @@
 		if(BUGMODE_LIST)
 			html = "<h3>Select a camera:</h3> <a href='?src=[REF(src)];view'>\[Cancel camera view\]</a><hr><table>"
 			for(var/entry in cameras)
-				var/obj/machinery/camera/C = cameras[entry]
-				if(QDELETED(C))
+				var/datum/weakref/camera_ref = cameras[entry]
+				var/obj/machinery/camera/camera = camera_ref.resolve()
+				if(!camera)
+					cameras -= camera_ref
 					continue
 				var/functions = ""
-				if(C.bug == src)
-					functions = " - <a href='?src=[REF(src)];monitor=[REF(C)]'>\[Monitor\]</a> <a href='?src=[REF(src)];emp=[REF(C)]'>\[Disable\]</a>"
+				if(camera.bug == src)
+					functions = " - <a href='?src=[REF(src)];monitor=[REF(camera_ref)]'>\[Monitor\]</a> <a href='?src=[REF(src)];emp=[REF(camera_ref)]'>\[Disable\]</a>"
 				else
-					functions = " - <a href='?src=[REF(src)];monitor=[REF(C)]'>\[Monitor\]</a>"
-				html += "<tr><td><a href='?src=[REF(src)];view=[REF(C)]'>[entry]</a></td><td>[functions]</td></tr>"
+					functions = " - <a href='?src=[REF(src)];monitor=[REF(camera_ref)]'>\[Monitor\]</a>"
+				html += "<tr><td><a href='?src=[REF(src)];view=[REF(camera_ref)]'>[entry]</a></td><td>[functions]</td></tr>"
 
 		if(BUGMODE_MONITOR)
 			if(current)
@@ -117,10 +123,11 @@
 				html = "Tracking '[tracked_name]'  <a href='?[REF(src)];mode=0'>\[Cancel Tracking\]</a>  <a href='?src=[REF(src)];view'>\[Cancel camera view\]</a><br>"
 				if(last_found)
 					var/time_diff = round((world.time - last_seen) / 150)
-					var/obj/machinery/camera/C = bugged_cameras[last_found]
+					var/datum/weakref/camera_ref = bugged_cameras[last_found]
+					var/obj/machinery/camera/camera = camera_ref.resolve()
 					var/outstring
-					if(C)
-						outstring = "<a href='?[REF(src)];view=[REF(C)]'>[last_found]</a>"
+					if(camera)
+						outstring = "<a href='?[REF(src)];view=[REF(camera_ref)]'>[last_found]</a>"
 					else
 						outstring = last_found
 					if(!time_diff)
@@ -132,8 +139,8 @@
 						if(!s)
 							s = "00"
 						html += "Last seen near [outstring] ([m]:[s] minute\s ago)<br>"
-					if( C && (C.bug == src)) //Checks to see if the camera has a bug
-						html += "<a href='?src=[REF(src)];emp=[REF(C)]'>\[Disable\]</a>"
+					if(camera && (camera.bug == src)) //Checks to see if the camera has a bug
+						html += "<a href='?src=[REF(src)];emp=[REF(camera_ref)]'>\[Disable\]</a>"
 
 				else
 					html += "Not yet seen."
@@ -204,12 +211,13 @@
 	if("monitor" in href_list)
 		//You can't locate on a list with keys
 		var/list/cameras = flatten_list(bugged_cameras)
-		var/obj/machinery/camera/C = locate(href_list["monitor"]) in cameras
-		if(C && istype(C))
-			if(!same_z_level(C))
+		var/datum/weakref/camera_ref = locate(href_list["monitor"]) in cameras
+		var/obj/machinery/camera/camera = camera_ref.resolve()
+		if(camera && istype(camera))
+			if(!same_z_level(camera))
 				return
 			track_mode = BUGMODE_MONITOR
-			current = C
+			current = camera
 			usr.reset_perspective(null)
 			interact()
 	if("track" in href_list)
@@ -225,13 +233,14 @@
 	if("emp" in href_list)
 		//You can't locate on a list with keys
 		var/list/cameras = flatten_list(bugged_cameras)
-		var/obj/machinery/camera/C = locate(href_list["emp"]) in cameras
-		if(C && istype(C) && C.bug == src)
-			if(!same_z_level(C))
+		var/datum/weakref/camera_ref = locate(href_list["emp"]) in cameras
+		var/obj/machinery/camera/camera = camera_ref.resolve()
+		if(camera && istype(camera) && camera.bug == src)
+			if(!same_z_level(camera))
 				return
-			C.emp_act(EMP_HEAVY)
-			C.bug = null
-			bugged_cameras -= C.c_tag
+			camera.emp_act(EMP_HEAVY)
+			camera.bug = null
+			bugged_cameras -= camera.c_tag
 		interact()
 		return
 	if("close" in href_list)
@@ -241,17 +250,18 @@
 	if("view" in href_list)
 		//You can't locate on a list with keys
 		var/list/cameras = flatten_list(bugged_cameras)
-		var/obj/machinery/camera/C = locate(href_list["view"]) in cameras
-		if(C && istype(C))
-			if(!same_z_level(C))
+		var/datum/weakref/camera_ref = locate(href_list["view"]) in cameras
+		var/obj/machinery/camera/camera = camera_ref.resolve()
+		if(camera && istype(camera))
+			if(!same_z_level(camera))
 				return
-			if(!C.can_use())
+			if(!camera.can_use())
 				to_chat(usr, span_warning("Something's wrong with that camera! You can't get a feed."))
 				return
-			current = C
+			current = camera
 			spawn(6)
 				if(src.check_eye(usr))
-					usr.reset_perspective(C)
+					usr.reset_perspective(camera)
 					interact()
 				else
 					usr.unset_machine()

code/game/objects/items/handcuffs.dm

@@ -479,6 +479,7 @@
 		var/obj/item/restraints/legcuffs/beartrap/B = new /obj/item/restraints/legcuffs/beartrap/energy/cyborg(get_turf(hit_atom))
 		B.spring_trap(null, hit_atom)
 		qdel(src)
+		return
 	. = ..()
 
 /**

code/game/objects/items/implants/implant_misc.dm

@@ -77,6 +77,10 @@
 		radio.keyslot = new radio_key
 	radio.recalculateChannels()
 
+/obj/item/implant/radio/Destroy()
+	QDEL_NULL(radio)
+	return ..()
+
 /obj/item/implant/radio/mining
 	radio_key = /obj/item/encryptionkey/headset_cargo
 

code/game/objects/items/stacks/sheets/glass.dm

@@ -61,11 +61,12 @@ GLOBAL_LIST_INIT(glass_recipes, list ( \
 		var/obj/item/stack/rods/V = W
 		if (V.get_amount() >= 1 && get_amount() >= 1)
 			var/obj/item/stack/sheet/rglass/RG = new (get_turf(user))
-			RG.add_fingerprint(user)
+			if(!QDELETED(RG))
+				RG.add_fingerprint(user)
 			var/replace = user.get_inactive_held_item()==src
 			V.use(1)
 			use(1)
-			if(QDELETED(src) && replace)
+			if(QDELETED(src) && replace && !QDELETED(RG))
 				user.put_in_hands(RG)
 		else
 			to_chat(user, span_warning("You need one rod and one sheet of glass to make reinforced glass!"))

code/game/objects/items/tanks/tanks.dm

@@ -86,9 +86,7 @@
 	return
 
 /obj/item/tank/Destroy()
-	if(air_contents)
-		QDEL_NULL(air_contents)
-
+	air_contents = null
 	STOP_PROCESSING(SSobj, src)
 	return ..()
 

code/game/objects/items/teleportation.dm

@@ -172,15 +172,17 @@
 	//SKYRAT EDIT END
 	var/list/locations = list()
 	for(var/obj/machinery/computer/teleporter/computer in GLOB.machines)
-		if(!computer.target)
+		var/atom/target = computer.target_ref?.resolve()
+		if(!target)
+			computer.target_ref = null
 			continue
-		var/area/computer_area = get_area(computer.target)
+		var/area/computer_area = get_area(target)
 		if(!computer_area || (computer_area.area_flags & NOTELEPORT))
 			continue
 		if(computer.power_station?.teleporter_hub && computer.power_station.engaged)
-			locations["[get_area(computer.target)] (Active)"] = computer
+			locations["[get_area(target)] (Active)"] = computer
 		else
-			locations["[get_area(computer.target)] (Inactive)"] = computer
+			locations["[get_area(target)] (Inactive)"] = computer
 
 	locations["None (Dangerous)"] = PORTAL_LOCATION_DANGEROUS
 
@@ -212,7 +214,7 @@
 		user.show_message(span_notice("[src] is recharging!"))
 		return
 
-	var/teleport_turf
+	var/atom/teleport_target
 
 	if (teleport_location == PORTAL_LOCATION_DANGEROUS)
 		var/list/dangerous_turfs = list()
@@ -226,16 +228,19 @@
 				continue
 			dangerous_turfs += dangerous_turf
 
-		teleport_turf = pick(dangerous_turfs)
+		teleport_target = pick(dangerous_turfs)
 	else
 		var/obj/machinery/computer/teleporter/computer = teleport_location
-		teleport_turf = computer.target
+		var/atom/target = computer.target_ref?.resolve()
+		if(!target)
+			computer.target_ref = null
+		teleport_target = target
 
-	if (teleport_turf == null)
+	if (teleport_target == null)
 		to_chat(user, span_notice("[src] vibrates, then stops. Maybe you should try something else."))
 		return
 
-	var/area/teleport_area = get_area(teleport_turf)
+	var/area/teleport_area = get_area(teleport_target)
 	if (teleport_area.area_flags & NOTELEPORT)
 		to_chat(user, span_notice("[src] is malfunctioning."))
 		return
@@ -243,7 +248,7 @@
 	if (!can_teleport_notifies(user))
 		return
 
-	var/list/obj/effect/portal/created = create_portal_pair(get_turf(user), get_teleport_turf(get_turf(teleport_turf)), 300, 1, null, atmos_link_override)
+	var/list/obj/effect/portal/created = create_portal_pair(get_turf(user), get_teleport_turf(get_turf(teleport_target)), 300, 1, null, atmos_link_override)
 	if(LAZYLEN(created) != 2)
 		return
 

code/game/objects/objs.dm

@@ -72,6 +72,7 @@
 				obj_flags &= ~string_to_objflag[flag]
 			else
 				obj_flags |= string_to_objflag[flag]
+				
 	if((obj_flags & ON_BLUEPRINTS) && isturf(loc))
 		var/turf/T = loc
 		T.add_blueprints_preround(src)

code/game/objects/structures/girders.dm

@@ -43,6 +43,7 @@
 			var/obj/item/stack/sheet/iron/M = new (loc, 2)
 			M.add_fingerprint(user)
 			qdel(src)
+			return
 
 	else if(istype(W, /obj/item/stack))
 		if(iswallturf(loc))
@@ -70,6 +71,7 @@
 					var/obj/structure/falsewall/iron/FW = new (loc)
 					transfer_fingerprints_to(FW)
 					qdel(src)
+					return
 			else
 				if(S.get_amount() < 5)
 					to_chat(user, span_warning("You need at least five rods to add plating!"))
@@ -104,6 +106,7 @@
 					var/obj/structure/falsewall/F = new (loc)
 					transfer_fingerprints_to(F)
 					qdel(src)
+					return
 			else if(state == GIRDER_REINF)
 				to_chat(user, span_warning("You can't finish a reinforced girder with regular iron. You need a plasteel sheet for that."))
 				return
@@ -137,6 +140,7 @@
 					var/obj/structure/falsewall/reinforced/FW = new (loc)
 					transfer_fingerprints_to(FW)
 					qdel(src)
+					return
 			else if(state == GIRDER_REINF)
 				if(S.get_amount() < 1)
 					return
@@ -183,6 +187,7 @@
 					var/obj/structure/falsewall/FW = new falsewall_type (loc)
 					transfer_fingerprints_to(FW)
 					qdel(src)
+					return
 			else
 				if(S.get_amount() < 2)
 					to_chat(user, span_warning("You need at least two sheets to add plating!"))

code/game/turfs/change_turf.dm

@@ -190,11 +190,9 @@ GLOBAL_LIST_INIT(blacklisted_automated_baseturfs, typecacheof(list(
 		var/datum/excited_group/stashed_group = excited_group
 		. = ..() //If path == type this will return us, don't bank on making a new type
 		if (!.) // changeturf failed or didn't do anything
-			QDEL_NULL(stashed_air)
 			return
 		var/turf/open/newTurf = .
 		newTurf.air.copy_from(stashed_air)
-		QDEL_NULL(stashed_air)
 		newTurf.excited = stashed_state
 		newTurf.excited_group = stashed_group
 		#ifdef VISUALIZE_ACTIVE_TURFS

code/game/turfs/turf.dm

@@ -524,7 +524,7 @@ GLOBAL_LIST_EMPTY(station_turfs)
 	LAZYADD(blueprint_data, I)
 
 /turf/proc/add_blueprints_preround(atom/movable/AM)
-	if(!SSticker.HasRoundStarted())
+	if(!SSicon_smooth.initialized)
 		if(AM.layer == WIRE_LAYER) //wires connect to adjacent positions after its parent init, meaning we need to wait (in this case, until smoothing) to take its image
 			SSicon_smooth.blueprint_queue += AM
 		else

code/modules/admin/verbs/diagnostics.dm

@@ -50,12 +50,16 @@
 			output += "&nbsp;&nbsp;<b>ERROR</b><br>"
 			continue
 		for (var/filter in fqs.devices)
-			var/list/f = fqs.devices[filter]
-			if (!f)
+			var/list/filtered = fqs.devices[filter]
+			if (!filtered)
 				output += "&nbsp;&nbsp;[filter]: ERROR<br>"
 				continue
-			output += "&nbsp;&nbsp;[filter]: [f.len]<br>"
-			for (var/device in f)
+			output += "&nbsp;&nbsp;[filter]: [filtered.len]<br>"
+			for(var/datum/weakref/device_ref as anything in filtered)
+				var/atom/device = device_ref.resolve()
+				if(!device)
+					filtered -= device_ref
+					continue
 				if (istype(device, /atom))
 					var/atom/A = device
 					output += "&nbsp;&nbsp;&nbsp;&nbsp;[device] ([AREACOORD(A)])<br>"

code/modules/antagonists/nukeop/nukeop.dm

@@ -187,7 +187,7 @@
 			dukinuki.forceMove(H.drop_location())
 		else
 			H.put_in_hands(dukinuki, TRUE)
-		nuke_team.war_button = dukinuki
+		nuke_team.war_button_ref = WEAKREF(dukinuki)
 	owner.announce_objectives()
 	addtimer(CALLBACK(src, .proc/nuketeam_name_assign), 1)
 
@@ -251,7 +251,7 @@
 	var/core_objective = /datum/objective/nuclear
 	var/memorized_code
 	var/list/team_discounts
-	var/obj/item/nuclear_challenge/war_button
+	var/datum/weakref/war_button_ref
 
 /datum/team/nuclear/New()
 	..()
@@ -394,7 +394,8 @@
 	disk_report += "</table>"
 	var/common_part = ..()
 	var/challenge_report
-	if(!QDELETED(war_button))
+	var/obj/item/nuclear_challenge/war_button = war_button_ref?.resolve()
+	if(war_button)
 		challenge_report += "<b>War not declared.</b> <a href='?_src_=holder;[HrefToken()];force_war=[REF(war_button)]'>\[Force war\]</a>"
 	return common_part + disk_report + challenge_report
 

code/modules/antagonists/traitor/equipment/Malf_Modules.dm

@@ -788,7 +788,8 @@ GLOBAL_LIST_INIT(malf_modules, subtypesof(/datum/ai_module))
 	var/upgraded_cameras = 0
 	for(var/V in GLOB.cameranet.cameras)
 		var/obj/machinery/camera/C = V
-		if(C.assembly)
+		var/obj/structure/camera_assembly/assembly = C.assembly_ref?.resolve()
+		if(assembly)
 			var/upgraded = FALSE
 
 			if(!C.isXRay())
@@ -803,7 +804,6 @@ GLOBAL_LIST_INIT(malf_modules, subtypesof(/datum/ai_module))
 
 			if(upgraded)
 				upgraded_cameras++
-
 	unlock_text = replacetext(unlock_text, "CAMSUPGRADED", "<b>[upgraded_cameras]</b>") //This works, since unlock text is called after upgrade()
 
 /// AI Turret Upgrade: Increases the health and damage of all turrets.

code/modules/atmospherics/machinery/components/components_base.dm

@@ -91,7 +91,7 @@
 /obj/machinery/atmospherics/components/nullifyNode(i)
 	if(parents[i])
 		nullifyPipenet(parents[i])
-	QDEL_NULL(airs[i])
+	airs[i] = null
 	return ..()
 
 /obj/machinery/atmospherics/components/on_construction()

code/modules/atmospherics/machinery/components/unary_devices/heat_exchanger.dm

@@ -10,7 +10,7 @@
 
 	layer = LOW_OBJ_LAYER
 
-	var/obj/machinery/atmospherics/components/unary/heat_exchanger/partner = null
+	var/datum/weakref/partner_ref = null
 	var/update_cycle
 
 	pipe_state = "heunary"
@@ -35,20 +35,26 @@
 	PIPING_LAYER_SHIFT(src, piping_layer)
 
 /obj/machinery/atmospherics/components/unary/heat_exchanger/atmosinit()
+	var/obj/machinery/atmospherics/components/unary/heat_exchanger/partner = partner_ref?.resolve()
 	if(!partner)
+		partner_ref = null
 		var/partner_connect = turn(dir,180)
 
 		for(var/obj/machinery/atmospherics/components/unary/heat_exchanger/target in get_step(src,partner_connect))
 			if(target.dir & get_dir(src,target))
-				partner = target
-				partner.partner = src
+				partner_ref = WEAKREF(target)
+				target.partner_ref = WEAKREF(src)
 				break
 
 	..()
 
 /obj/machinery/atmospherics/components/unary/heat_exchanger/process_atmos()
 	..()
-	if(!partner || SSair.times_fired <= update_cycle)
+	var/obj/machinery/atmospherics/components/unary/heat_exchanger/partner = partner_ref?.resolve()
+	if(!partner)
+		partner_ref = null
+		return
+	if(SSair.times_fired <= update_cycle)
 		return
 
 	update_cycle = SSair.times_fired

code/modules/atmospherics/machinery/pipes/pipes.dm

@@ -82,7 +82,6 @@
 	QDEL_NULL(parent)
 
 	releaseAirToTurf()
-	QDEL_NULL(air_temporary)
 
 	var/turf/T = loc
 	for(var/obj/machinery/meter/meter in T)

code/modules/atmospherics/machinery/portable/portable_atmospherics.dm

@@ -26,7 +26,7 @@
 
 /obj/machinery/portable_atmospherics/Destroy()
 	disconnect()
-	QDEL_NULL(air_contents)
+	air_contents = null
 	SSair.stop_processing_machine(src)
 
 	return ..()

code/modules/buildmode/buildmode.dm

@@ -45,8 +45,10 @@
 /datum/buildmode/Destroy()
 	close_switchstates()
 	holder.player_details.post_login_callbacks -= li_cb
+	li_cb = null
 	holder = null
 	QDEL_NULL(mode)
+	QDEL_LIST(buttons)
 	QDEL_LIST(modeswitch_buttons)
 	QDEL_LIST(dirswitch_buttons)
 	return ..()

code/modules/clothing/shoes/_shoes.dm

@@ -19,8 +19,8 @@
 	var/tied = SHOES_TIED
 	///How long it takes to lace/unlace these shoes
 	var/lace_time = 5 SECONDS
-	///any alerts we have active
-	var/atom/movable/screen/alert/our_alert
+	///An active alert
+	var/datum/weakref/our_alert_ref
 
 /obj/item/clothing/shoes/suicide_act(mob/living/carbon/user)
 	if(rand(2)>1)
@@ -76,7 +76,7 @@
 /obj/item/clothing/shoes/equipped(mob/user, slot)
 	. = ..()
 	if(can_be_tied && tied == SHOES_UNTIED)
-		our_alert = user.throw_alert("shoealert", /atom/movable/screen/alert/shoes/untied)
+		our_alert_ref = WEAKREF(user.throw_alert("shoealert", /atom/movable/screen/alert/shoes/untied))
 		RegisterSignal(src, COMSIG_SHOES_STEP_ACTION, .proc/check_trip, override=TRUE)
 
 /obj/item/clothing/shoes/proc/restore_offsets(mob/user)
@@ -85,7 +85,10 @@
 	worn_y_dimension = world.icon_size
 
 /obj/item/clothing/shoes/dropped(mob/user)
-	if(our_alert && our_alert.owner == user)
+	var/atom/movable/screen/alert/our_alert = our_alert_ref?.resolve()
+	if(!our_alert)
+		our_alert_ref = null
+	if(our_alert?.owner == user)
 		user.clear_alert("shoealert")
 	if(offset && equipped_before_drop)
 		restore_offsets(user)
@@ -125,7 +128,7 @@
 		UnregisterSignal(src, COMSIG_SHOES_STEP_ACTION)
 	else
 		if(tied == SHOES_UNTIED && our_guy && user == our_guy)
-			our_alert = our_guy.throw_alert("shoealert", /atom/movable/screen/alert/shoes/untied) // if we're the ones unknotting our own laces, of course we know they're untied
+			our_alert_ref = WEAKREF(our_guy.throw_alert("shoealert", /atom/movable/screen/alert/shoes/untied)) // if we're the ones unknotting our own laces, of course we know they're untied
 		RegisterSignal(src, COMSIG_SHOES_STEP_ACTION, .proc/check_trip, override=TRUE)
 
 /**
@@ -216,7 +219,7 @@
 		our_guy.Knockdown(10)
 		our_guy.visible_message(span_danger("[our_guy] trips on [our_guy.p_their()] knotted shoelaces and falls! What a klutz!"), span_userdanger("You trip on your knotted shoelaces and fall over!"))
 		SEND_SIGNAL(our_guy, COMSIG_ADD_MOOD_EVENT, "trip", /datum/mood_event/tripped) // well we realized they're knotted now!
-		our_alert = our_guy.throw_alert("shoealert", /atom/movable/screen/alert/shoes/knotted)
+		our_alert_ref = WEAKREF(our_guy.throw_alert("shoealert", /atom/movable/screen/alert/shoes/knotted))
 
 	else if(tied ==  SHOES_UNTIED)
 		var/wiser = TRUE // did we stumble and realize our laces are undone?
@@ -248,7 +251,7 @@
 				wiser = FALSE
 		if(wiser)
 			SEND_SIGNAL(our_guy, COMSIG_ADD_MOOD_EVENT, "untied", /datum/mood_event/untied) // well we realized they're untied now!
-			our_alert = our_guy.throw_alert("shoealert", /atom/movable/screen/alert/shoes/untied)
+			our_alert_ref = WEAKREF(our_guy.throw_alert("shoealert", /atom/movable/screen/alert/shoes/untied))
 
 
 /obj/item/clothing/shoes/attack_hand(mob/living/carbon/human/user, list/modifiers)

code/modules/detectivework/detective_work.dm

@@ -77,8 +77,9 @@
 	var/obj/effect/decal/cleanable/blood/splatter/B = locate() in src
 	if(QDELETED(B)) // SKYRAT EDIT - SANITY CHECK; DONT ADD DNA TO A FUCKING DELETED BLOOD SPATTER - original: if(!B)
 		B = new /obj/effect/decal/cleanable/blood/splatter(src, diseases)
-	B.add_blood_DNA(blood_dna) //give blood info to the blood decal.
-	return TRUE //we bloodied the floor
+	if(!QDELETED(B))
+		B.add_blood_DNA(blood_dna) //give blood info to the blood decal.
+		return TRUE //we bloodied the floor
 
 /mob/living/carbon/human/add_blood_DNA(list/blood_dna, list/datum/disease/diseases)
 	if(wear_suit)

code/modules/mob/login.dm

@@ -48,6 +48,9 @@
 	if(!client)
 		return FALSE
 
+	//We do this here to prevent hanging refs from ghostize or whatever, since if we were in another mob before this'll take care of it
+	clear_client_in_contents()
+
 	SEND_SIGNAL(src, COMSIG_MOB_LOGIN)
 
 	if (key != client.key)

code/modules/mob/mob.dm

@@ -43,7 +43,6 @@
 			observe.reset_perspective(null)
 	qdel(hud_used)
 	QDEL_LIST(client_colours)
-	clear_client_in_contents() //Gotta do this here as well as Logout, since client will be null by the time it gets there, cause of that ghostize
 	ghostize() //False, since we're deleting it currently
 	if(mind?.current == src) //Let's just be safe yeah? This will occasionally be cleared, but not always. Can't do it with ghostize without changing behavior
 		mind.set_current(null)

code/modules/plumbing/ducts.dm

@@ -61,7 +61,7 @@ All the important duct code:
 		if(D == src)
 			continue
 		if(D.duct_layer & duct_layer)
-			disconnect_duct()
+			return INITIALIZE_HINT_QDEL //If we have company, end it all
 
 	attempt_connect()
 	AddElement(/datum/element/undertile, TRAIT_T_RAY_VISIBLE)
@@ -166,8 +166,9 @@ All the important duct code:
 	lose_neighbours()
 	reset_connects(0)
 	update_appearance()
-	if(ispath(drop_on_wrench) && !QDELING(src))
+	if(ispath(drop_on_wrench))
 		new drop_on_wrench(drop_location())
+	if(!QDELETED(src))
 		qdel(src)
 
 ///Special proc to draw a new connect frame based on neighbours. not the norm so we can support multiple duct kinds

code/modules/projectiles/ammunition/_ammunition.dm

@@ -51,12 +51,11 @@
 	update_appearance()
 
 /obj/item/ammo_casing/Destroy()
-	. = ..()
-
 	var/turf/T = get_turf(src)
 	if(T && !loaded_projectile && is_station_level(T.z))
 		SSblackbox.record_feedback("tally", "station_mess_destroyed", 1, name)
 	QDEL_NULL(loaded_projectile)
+	return ..()
 
 /obj/item/ammo_casing/add_weapon_description()
 	AddElement(/datum/element/weapon_description, attached_proc = .proc/add_notes_ammo)

code/modules/projectiles/projectile/energy/net_snare.dm

@@ -33,9 +33,12 @@
 	. = ..()
 	var/obj/item/beacon/teletarget = null
 	for(var/obj/machinery/computer/teleporter/com in GLOB.machines)
-		if(com.target)
+		var/atom/target = com.target_ref.resolve()
+		if(target)
 			if(com.power_station && com.power_station.teleporter_hub && com.power_station.engaged)
-				teletarget = com.target
+				teletarget = target
+		else
+			com.target_ref = null
 
 	addtimer(CALLBACK(src, .proc/pop, teletarget), 30)
 

code/modules/reagents/chemistry/reagents/other_reagents.dm

@@ -2066,12 +2066,20 @@
 	taste_description = "rainbows"
 	var/can_colour_mobs = TRUE
 	chemical_flags = REAGENT_CAN_BE_SYNTHESIZED
+	var/datum/callback/color_callback
 
 /datum/reagent/colorful_reagent/New()
-	SSticker.OnRoundstart(CALLBACK(src,.proc/UpdateColor))
+	color_callback = CALLBACK(src, .proc/UpdateColor)
+	SSticker.OnRoundstart(color_callback)
+	return ..()
+
+/datum/reagent/colorful_reagent/Destroy()
+	LAZYREMOVE(SSticker.round_end_events, color_callback) //Prevents harddels during roundstart
+	color_callback = null //Fly free little callback
 	return ..()
 
 /datum/reagent/colorful_reagent/proc/UpdateColor()
+	color_callback = null
 	color = pick(random_color_list)
 
 /datum/reagent/colorful_reagent/on_mob_life(mob/living/carbon/M, delta_time, times_fired)

code/modules/recycling/disposal/holder.dm

@@ -16,7 +16,6 @@
 	var/hasmob = FALSE // contains a mob
 
 /obj/structure/disposalholder/Destroy()
-	QDEL_NULL(gas)
 	active = FALSE
 	return ..()
 

code/modules/station_goals/bsa.dm

@@ -65,8 +65,8 @@
 	name = "Bluespace Artillery Fusor"
 	desc = "Contents classified by Nanotrasen Naval Command. Needs to be linked with the other BSA parts using a multitool."
 	icon_state = "fuel_chamber"
-	var/obj/machinery/bsa/back/back
-	var/obj/machinery/bsa/front/front
+	var/datum/weakref/back_ref
+	var/datum/weakref/front_ref
 
 /obj/machinery/bsa/middle/multitool_act(mob/living/user, obj/item/I)
 	if(!multitool_check_buffer(user, I))
@@ -74,18 +74,20 @@
 	var/obj/item/multitool/M = I
 	if(M.buffer)
 		if(istype(M.buffer, /obj/machinery/bsa/back))
-			back = M.buffer
+			back_ref = WEAKREF(M.buffer)
+			to_chat(user, span_notice("You link [src] with [M.buffer]."))
 			M.buffer = null
-			to_chat(user, span_notice("You link [src] with [back]."))
 		else if(istype(M.buffer, /obj/machinery/bsa/front))
-			front = M.buffer
+			front_ref = WEAKREF(M.buffer)
+			to_chat(user, span_notice("You link [src] with [M.buffer]."))
 			M.buffer = null
-			to_chat(user, span_notice("You link [src] with [front]."))
 	else
 		to_chat(user, span_warning("[I]'s data buffer is empty!"))
 	return TRUE
 
 /obj/machinery/bsa/middle/proc/check_completion()
+	var/obj/machinery/bsa/front/front = front_ref?.resolve()
+	var/obj/machinery/bsa/back/back = back_ref?.resolve()
 	if(!front || !back)
 		return "No linked parts detected!"
 	if(!front.anchored || !back.anchored || !anchored)
@@ -113,6 +115,10 @@
 	return TRUE
 
 /obj/machinery/bsa/middle/proc/get_cannon_direction()
+	var/obj/machinery/bsa/front/front = front_ref?.resolve()
+	var/obj/machinery/bsa/back/back = back_ref?.resolve()
+	if(!front || !back)
+		return
 	if(front.x > x && back.x < x)
 		return EAST
 	else if(front.x < x && back.x > x)
@@ -237,7 +243,7 @@
 	icon_state = "control_boxp"
 	icon_keyboard = ""
 
-	var/obj/machinery/bsa/full/cannon
+	var/datum/weakref/cannon_ref
 	var/notice
 	var/target
 	var/area_aim = FALSE //should also show areas for targeting
@@ -252,6 +258,7 @@
 		ui.open()
 
 /obj/machinery/computer/bsa_control/ui_data()
+	var/obj/machinery/bsa/full/cannon = cannon_ref?.resolve()
 	var/list/data = list()
 	data["ready"] = cannon ? cannon.ready : FALSE
 	data["connected"] = cannon
@@ -268,7 +275,7 @@
 
 	switch(action)
 		if("build")
-			cannon = deploy()
+			cannon_ref = WEAKREF(deploy())
 			. = TRUE
 		if("fire")
 			fire(usr)
@@ -308,6 +315,10 @@
 		return get_turf(G.parent)
 
 /obj/machinery/computer/bsa_control/proc/fire(mob/user)
+	var/obj/machinery/bsa/full/cannon = cannon_ref?.resolve()
+	if(!cannon)
+		notice = "No Cannon Exists!"
+		return
 	if(cannon.machine_stat)
 		notice = "Cannon unpowered!"
 		return
@@ -331,8 +342,8 @@
 	s.set_up(4,get_turf(centerpiece))
 	s.start()
 	var/obj/machinery/bsa/full/cannon = new(get_turf(centerpiece),centerpiece.get_cannon_direction())
-	qdel(centerpiece.front)
-	qdel(centerpiece.back)
+	QDEL_NULL(centerpiece.front_ref)
+	QDEL_NULL(centerpiece.back_ref)
 	qdel(centerpiece)
 	return cannon
 */

code/modules/tgui/tgui.dm

@@ -63,6 +63,11 @@
 	if(ui_x && ui_y)
 		src.window_size = list(ui_x, ui_y)
 
+/datum/tgui/Destroy()
+	user = null
+	src_object = null
+	return ..()
+
 /**
  * public
  *