Fix various segfaults caused by missing P_MobjWasRemoved checks

src/p_enemy.c

@@ -541,7 +541,7 @@ boolean P_Move(mobj_t *actor, fixed_t speed)
 
 	if (!P_TryMove(actor, tryx, tryy, false))
 	{
-		if (actor->flags & MF_FLOAT && floatok)
+		if (!P_MobjWasRemoved(actor) && actor->flags & MF_FLOAT && floatok)
 		{
 			// must adjust height
 			if (actor->z < tmfloorz)
@@ -585,6 +585,7 @@ void P_NewChaseDir(mobj_t *actor)
 	dirtype_t d[3];
 	dirtype_t tdir = DI_NODIR, olddir, turnaround;
 
+	I_Assert(!P_MobjWasRemoved(actor));
 	I_Assert(actor->target != NULL);
 	I_Assert(!P_MobjWasRemoved(actor->target));
 
@@ -623,7 +624,7 @@ void P_NewChaseDir(mobj_t *actor)
 		dirtype_t newdir = diags[((deltay < 0)<<1) + (deltax > 0)];
 
 		actor->movedir = newdir;
-		if ((newdir != turnaround) && P_TryWalk(actor))
+		if ((newdir != turnaround) && (P_TryWalk(actor) || P_MobjWasRemoved(actor)))
 			return;
 	}
 
@@ -644,7 +645,7 @@ void P_NewChaseDir(mobj_t *actor)
 	{
 		actor->movedir = d[1];
 
-		if (P_TryWalk(actor))
+		if (P_TryWalk(actor) || P_MobjWasRemoved(actor))
 			return; // either moved forward or attacked
 	}
 
@@ -652,7 +653,7 @@ void P_NewChaseDir(mobj_t *actor)
 	{
 		actor->movedir = d[2];
 
-		if (P_TryWalk(actor))
+		if (P_TryWalk(actor) || P_MobjWasRemoved(actor))
 			return;
 	}
 
@@ -661,7 +662,7 @@ void P_NewChaseDir(mobj_t *actor)
 	{
 		actor->movedir =olddir;
 
-		if (P_TryWalk(actor))
+		if (P_TryWalk(actor) || P_MobjWasRemoved(actor))
 			return;
 	}
 
@@ -674,7 +675,7 @@ void P_NewChaseDir(mobj_t *actor)
 			{
 				actor->movedir = tdir;
 
-				if (P_TryWalk(actor))
+				if (P_TryWalk(actor) || P_MobjWasRemoved(actor))
 					return;
 			}
 		}
@@ -687,7 +688,7 @@ void P_NewChaseDir(mobj_t *actor)
 			{
 				actor->movedir = tdir;
 
-				if (P_TryWalk(actor))
+				if (P_TryWalk(actor) || P_MobjWasRemoved(actor))
 					return;
 			}
 		}
@@ -697,7 +698,7 @@ void P_NewChaseDir(mobj_t *actor)
 	{
 		actor->movedir = turnaround;
 
-		if (P_TryWalk(actor))
+		if (P_TryWalk(actor) || P_MobjWasRemoved(actor))
 			return;
 	}
 
@@ -1100,7 +1101,7 @@ nomissile:
 		return; // got a new target
 
 	// chase towards player
-	if (--actor->movecount < 0 || !P_Move(actor, actor->info->speed))
+	if (--actor->movecount < 0 || (!P_Move(actor, actor->info->speed) && !P_MobjWasRemoved(actor)))
 		P_NewChaseDir(actor);
 }
 
@@ -1188,7 +1189,7 @@ nomissile:
 		return; // got a new target
 
 	// chase towards player
-	if (--actor->movecount < 0 || !P_Move(actor, actor->info->speed))
+	if (--actor->movecount < 0 || (!P_Move(actor, actor->info->speed) && !P_MobjWasRemoved(actor)))
 		P_NewChaseDir(actor);
 }
 
@@ -1267,7 +1268,8 @@ void A_FaceStabRev(mobj_t *actor)
 		else
 		{
 			P_TryMove(actor, actor->x - P_ReturnThrustX(actor, actor->angle, 2<<FRACBITS), actor->y - P_ReturnThrustY(actor, actor->angle, 2<<FRACBITS), false);
-			P_FaceStabFlume(actor);
+			if (!P_MobjWasRemoved(actor))
+				P_FaceStabFlume(actor);
 		}
 	}
 }
@@ -1333,8 +1335,9 @@ void A_FaceStabHurl(mobj_t *actor)
 
 				while (step > 0)
 				{
-					if (!hwork->hnext)
+					if (P_MobjWasRemoved(hwork->hnext))
 						P_SetTarget(&hwork->hnext, P_SpawnMobjFromMobj(actor, 0, 0, 0, MT_FACESTABBERSPEAR));
+
 					if (!P_MobjWasRemoved(hwork->hnext))
 					{
 						hwork = hwork->hnext;
@@ -1343,6 +1346,20 @@ void A_FaceStabHurl(mobj_t *actor)
 						P_SetScale(hwork, hwork->destscale);
 						hwork->fuse = 2;
 						P_MoveOrigin(hwork, actor->x + xo*(15-step), actor->y + yo*(15-step), actor->z + (actor->height - hwork->height)/2 + (P_MobjFlip(actor)*(8<<FRACBITS)));
+						if (P_MobjWasRemoved(hwork))
+						{
+							// if one of the sections are removed, erase the entire damn thing.
+							mobj_t *hnext = actor->hnext;
+							hwork = actor;
+							do
+							{
+								hnext = hwork->hnext;
+								P_RemoveMobj(hwork);
+								hwork = hnext;
+							}
+							while (!P_MobjWasRemoved(hwork));
+							return;
+						}
 					}
 					step -= NUMGRADS;
 				}
@@ -1359,11 +1376,14 @@ void A_FaceStabHurl(mobj_t *actor)
 #undef NUMGRADS
 #undef NUMSTEPS
 			}
+			if (P_MobjWasRemoved(actor))
+				return;
 		}
 	}
 
 	P_SetMobjState(actor, locvar2);
-	actor->reactiontime = actor->info->reactiontime;
+	if (!P_MobjWasRemoved(actor))
+		actor->reactiontime = actor->info->reactiontime;
 }
 
 // Function: A_FaceStabMiss
@@ -1393,6 +1413,8 @@ void A_FaceStabMiss(mobj_t *actor)
 		actor->y + P_ReturnThrustY(actor, actor->angle, actor->extravalue2<<FRACBITS),
 		false))
 	{
+		if (P_MobjWasRemoved(actor))
+			return;
 		actor->extravalue2 = 0;
 		P_SetMobjState(actor, locvar2);
 	}
@@ -1425,6 +1447,8 @@ void A_StatueBurst(mobj_t *actor)
 	P_SetTarget(&new->target, actor->target);
 	if (locvar2)
 		P_SetMobjState(new, (statenum_t)locvar2);
+	if (P_MobjWasRemoved(new))
+		return;
 	S_StartSound(new, new->info->attacksound);
 	S_StopSound(actor);
 	S_StartSound(actor, sfx_s3k96);
@@ -1520,7 +1544,7 @@ void A_JetJawChomp(mobj_t *actor)
 	}
 
 	// chase towards player
-	if (--actor->movecount < 0 || !P_Move(actor, actor->info->speed))
+	if (--actor->movecount < 0 || (!P_Move(actor, actor->info->speed) && !P_MobjWasRemoved(actor)))
 		P_NewChaseDir(actor);
 }
 
@@ -1941,14 +1965,15 @@ void A_SharpChase(mobj_t *actor)
 		}
 
 		// chase towards player
-		if (--actor->movecount < 0 || !P_Move(actor, actor->info->speed))
+		if (--actor->movecount < 0 || (!P_Move(actor, actor->info->speed) && !P_MobjWasRemoved(actor)))
 			P_NewChaseDir(actor);
 	}
 	else
 	{
 		actor->threshold = actor->info->painchance;
 		P_SetMobjState(actor, actor->info->missilestate);
-		S_StartSound(actor, actor->info->attacksound);
+		if (!P_MobjWasRemoved(actor))
+			S_StartSound(actor, actor->info->attacksound);
 	}
 }
 
@@ -2034,6 +2059,8 @@ void A_CrushstaceanWalk(mobj_t *actor)
 		false)
 	|| (actor->reactiontime-- <= 0))
 	{
+		if (P_MobjWasRemoved(actor))
+			return;
 		actor->flags2 ^= MF2_AMBUSH;
 		P_SetTarget(&actor->target, NULL);
 		P_SetMobjState(actor, locvar2);
@@ -2215,6 +2242,8 @@ void A_CrushclawLaunch(mobj_t *actor)
 		true)
 		&& !locvar1)
 	{
+		if (P_MobjWasRemoved(actor))
+			return;
 		actor->extravalue1 = 0;
 		actor->extravalue2 = FixedHypot(actor->x - actor->target->x, actor->y - actor->target->y)>>FRACBITS;
 		P_SetMobjState(actor, locvar2);
@@ -2223,6 +2252,8 @@ void A_CrushclawLaunch(mobj_t *actor)
 	}
 	else
 	{
+		if (P_MobjWasRemoved(actor))
+			return;
 		actor->z = actor->target->z;
 		if ((!locvar1 && (actor->extravalue2 > 256)) || (locvar1 && (actor->extravalue2 < 16)))
 		{
@@ -2648,7 +2679,7 @@ nomissile:
 		return; // got a new target
 
 	// chase towards player
-	if (--actor->movecount < 0 || !P_Move(actor, actor->info->speed))
+	if (--actor->movecount < 0 || (!P_Move(actor, actor->info->speed) && !P_MobjWasRemoved(actor)))
 		P_NewChaseDir(actor);
 }
 
@@ -5788,7 +5819,11 @@ void A_MinusDigging(mobj_t *actor)
 	if (P_AproxDistance(actor->x - actor->target->x, actor->y - actor->target->y) < actor->radius*2)
 	{
 		P_SetMobjState(actor, actor->info->meleestate);
+		if (P_MobjWasRemoved(actor))
+			return;
 		P_TryMove(actor, actor->target->x, actor->target->y, false);
+		if (P_MobjWasRemoved(actor))
+			return;
 		S_StartSound(actor, actor->info->attacksound);
 
 		// Spawn growing dirt pile.
@@ -5796,6 +5831,8 @@ void A_MinusDigging(mobj_t *actor)
 		if (P_MobjWasRemoved(par))
 			return;
 		P_SetMobjState(par, actor->info->raisestate);
+		if (P_MobjWasRemoved(par))
+			return;
 		P_SetScale(par, actor->scale*2);
 		if (actor->eflags & MFE_VERTICALFLIP)
 			par->eflags |= MFE_VERTICALFLIP;
@@ -5809,6 +5846,8 @@ void A_MinusDigging(mobj_t *actor)
 	// Move
 	var1 = 3;
 	A_Chase(actor);
+	if (P_MobjWasRemoved(actor))
+		return;
 
 	// Carry over shit, maybe
 	if (P_MobjWasRemoved(actor->tracer) || !actor->tracer->health)
@@ -5832,7 +5871,7 @@ void A_MinusDigging(mobj_t *actor)
 	{
 		if (P_TryMove(actor->tracer, actor->x, actor->y, false))
 			actor->tracer->z = mz;
-		else
+		else if (!P_MobjWasRemoved(actor))
 			P_SetTarget(&actor->tracer, NULL);
 	}
 }
@@ -7304,7 +7343,7 @@ nomissile:
 	// chase towards player
 	if (P_AproxDistance(actor->target->x-actor->x, actor->target->y-actor->y) > actor->radius+actor->target->radius)
 	{
-		if (--actor->movecount < 0 || !P_Move(actor, actor->info->speed))
+		if (--actor->movecount < 0 || (!P_Move(actor, actor->info->speed) && !P_MobjWasRemoved(actor)))
 			P_NewChaseDir(actor);
 	}
 	// too close, don't want to chase.
@@ -7661,7 +7700,7 @@ void A_Boss7Chase(mobj_t *actor)
 	if (leveltime & 1)
 	{
 		// chase towards player
-		if (--actor->movecount < 0 || !P_Move(actor, actor->info->speed))
+		if (--actor->movecount < 0 || (!P_Move(actor, actor->info->speed) && !P_MobjWasRemoved(actor)))
 			P_NewChaseDir(actor);
 	}
 }
@@ -8119,6 +8158,8 @@ void A_GuardChase(mobj_t *actor)
 			false)
 		&& speed > 0) // can't be the same check as previous so that P_TryMove gets to happen.
 		{
+			if (P_MobjWasRemoved(actor))
+				return;
 			INT32 direction = actor->spawnpoint ? actor->spawnpoint->args[0] : TMGD_BACK;
 
 			switch (direction)
@@ -8135,6 +8176,8 @@ void A_GuardChase(mobj_t *actor)
 					break;
 			}
 		}
+		if (P_MobjWasRemoved(actor))
+			return;
 
 		if (actor->extravalue1 < actor->info->speed)
 			actor->extravalue1++;
@@ -8171,7 +8214,11 @@ void A_GuardChase(mobj_t *actor)
 		// chase towards player
 		if (--actor->movecount < 0 || !P_Move(actor, (actor->flags2 & MF2_AMBUSH) ? actor->info->speed * 2 : actor->info->speed))
 		{
+			if (P_MobjWasRemoved(actor))
+				return;
 			P_NewChaseDir(actor);
+			if (P_MobjWasRemoved(actor))
+				return;
 			actor->movecount += 5; // Increase tics before change in direction allowed.
 		}
 	}
@@ -8641,6 +8688,9 @@ void A_PlaySeeSound(mobj_t *actor)
 	if (LUA_CallAction(A_PLAYSEESOUND, actor))
 		return;
 
+	if (P_MobjWasRemoved(actor))
+		return;
+
 	if (actor->info->seesound)
 		S_StartScreamSound(actor, actor->info->seesound);
 }
@@ -11735,7 +11785,13 @@ void A_BrakChase(mobj_t *actor)
 
 	// chase towards player
 	if (--actor->movecount < 0 || !P_Move(actor, actor->info->speed))
+	{
+		if (P_MobjWasRemoved(actor))
+			return;
 		P_NewChaseDir(actor);
+		if (P_MobjWasRemoved(actor))
+			return;
+	}
 
 	// Optionally play a sound effect
 	if (locvar2 > 0 && locvar2 < NUMSFX)
@@ -13314,6 +13370,8 @@ void A_DoNPCSkid(mobj_t *actor)
 	if ((FixedHypot(actor->momx, actor->momy) < locvar2)
 	|| !P_TryMove(actor, actor->x + actor->momx, actor->y + actor->momy, false))
 	{
+		if (P_MobjWasRemoved(actor))
+			return;
 		actor->momx = actor->momy = 0;
 		P_SetMobjState(actor, locvar1);
 		return;
@@ -13856,6 +13914,8 @@ static boolean PIT_DustDevilLaunch(mobj_t *thing)
 				y = dustdevil->y;
 			}
 			P_TryMove(thing, x - thing->momx, y - thing->momy, true);
+			if (P_MobjWasRemoved(thing))
+				return false;
 		}
 		else
 		{ //Player on the top of the tornado.
@@ -14260,6 +14320,8 @@ static void P_SnapperLegPlace(mobj_t *mo)
 
 	seg->z = mo->z + ((mo->eflags & MFE_VERTICALFLIP) ? (((mo->height<<1)/3) - seg->height) : mo->height/3);
 	P_TryMove(seg, mo->x + FixedMul(c, rad) + necklen*c, mo->y + FixedMul(s, rad) + necklen*s, true);
+	if (P_MobjWasRemoved(seg))
+		return;
 	seg->angle = a;
 
 	// Move as many legs as available.
@@ -14281,6 +14343,8 @@ static void P_SnapperLegPlace(mobj_t *mo)
 			y = s*o2 - c*o1;
 			seg->z = mo->z + (((mo->eflags & MFE_VERTICALFLIP) ? (mo->height - seg->height) : 0));
 			P_TryMove(seg, mo->x + x, mo->y + y, true);
+			if (P_MobjWasRemoved(seg))
+				return;
 			P_SetMobjState(seg, seg->info->raisestate);
 		}
 		else
@@ -14424,6 +14488,8 @@ void A_SnapperThinker(mobj_t *actor)
 		s = FINESINE(fa);
 
 		P_TryMove(actor, actor->x + c*speed, actor->y + s*speed, false);
+		if (P_MobjWasRemoved(actor))
+			return;
 
 		// The snapper spawns dust if going fast!
 		if (actor->reactiontime < 4)

src/p_inter.c

@@ -1397,11 +1397,14 @@ void P_TouchSpecialThing(mobj_t *special, mobj_t *toucher, boolean heightcheck)
 			i = 0;
 			for (; special->type == MT_HOOP; special = special->hnext)
 			{
-				special->fuse = 11;
+				if (!P_MobjWasRemoved(special->target))
-				special->movedir = i;
+				{
-				special->extravalue1 = special->target->extravalue1;
+					special->fuse = 11;
-				special->extravalue2 = special->target->extravalue2;
+					special->movedir = i;
-				special->target->threshold = 4242;
+					special->extravalue1 = special->target->extravalue1;
+					special->extravalue2 = special->target->extravalue2;
+					special->target->threshold = 4242;
+				}
 				i++;
 			}
 			// Make the collision detectors disappear.

src/p_map.c

@@ -2734,7 +2734,7 @@ increment_move
 				tryy = y;
 		}
 
-		if (!P_CheckPosition(thing, tryx, tryy))
+		if (!P_CheckPosition(thing, tryx, tryy) || P_MobjWasRemoved(thing))
 			return false; // solid wall or thing
 
 		if (!(thing->flags & MF_NOCLIP))
@@ -2958,6 +2958,7 @@ boolean P_TryMove(mobj_t *thing, fixed_t x, fixed_t y, boolean allowdropoff)
 boolean P_SceneryTryMove(mobj_t *thing, fixed_t x, fixed_t y)
 {
 	fixed_t tryx, tryy;
+	I_Assert(!P_MobjWasRemoved(thing));
 
 	tryx = thing->x;
 	tryy = thing->y;
@@ -2975,7 +2976,7 @@ boolean P_SceneryTryMove(mobj_t *thing, fixed_t x, fixed_t y)
 		else
 			tryy = y;
 
-		if (!P_CheckPosition(thing, tryx, tryy))
+		if (!P_CheckPosition(thing, tryx, tryy) || P_MobjWasRemoved(thing))
 			return false; // solid wall or thing
 
 		if (!(thing->flags & MF_NOCLIP))
@@ -3714,6 +3715,12 @@ static void P_CheckLavaWall(mobj_t *mo, sector_t *sec)
 	}
 }
 
+static inline void P_StairStepSlideMove(mobj_t *mo)
+{
+	if (!P_TryMove(mo, mo->x, mo->y + mo->momy, true) && !P_MobjWasRemoved(mo)) //Allow things to drop off.
+		P_TryMove(mo, mo->x + mo->momx, mo->y, true);
+}
+
 //
 // P_SlideMove
 // The momx / momy move is bad, so try to slide
@@ -3735,6 +3742,8 @@ void P_SlideMove(mobj_t *mo)
 
 	memset(&junk, 0x00, sizeof(junk));
 
+	I_Assert(!P_MobjWasRemoved(mo));
+
 	if (tmhitthing && mo->z + mo->height > tmhitthing->z && mo->z < tmhitthing->z + tmhitthing->height)
 	{
 		// Don't mess with your momentum if it's a pushable object. Pushables do their own crazy things already.
@@ -3869,7 +3878,10 @@ void P_SlideMove(mobj_t *mo)
 
 retry:
 	if ((++hitcount == 3) || papercol)
-		goto stairstep; // don't loop forever
+	{
+		P_StairStepSlideMove(mo);
+		return;
+	}
 
 	// trace along the three leading corners
 	if (mo->momx > 0)
@@ -3921,9 +3933,7 @@ papercollision:
 	if (bestslidefrac == FRACUNIT+1)
 	{
 		// the move must have hit the middle, so stairstep
-stairstep:
+		P_StairStepSlideMove(mo);
-		if (!P_TryMove(mo, mo->x, mo->y + mo->momy, true)) //Allow things to drop off.
-			P_TryMove(mo, mo->x + mo->momx, mo->y, true);
 		return;
 	}
 
@@ -3935,7 +3945,13 @@ stairstep:
 		newy = FixedMul(mo->momy, bestslidefrac);
 
 		if (!P_TryMove(mo, mo->x + newx, mo->y + newy, true))
-			goto stairstep;
+		{
+			if (!P_MobjWasRemoved(mo))
+				P_StairStepSlideMove(mo);
+			return;
+		}
+		if (P_MobjWasRemoved(mo))
+			return;
 	}
 
 	// Now continue along the wall.
@@ -3986,11 +4002,13 @@ stairstep:
 			tmymove = 0;
 		}
 		if (!P_TryMove(mo, newx, newy, true)) {
-			if (success)
+			if (success || P_MobjWasRemoved(mo))
 				return; // Good enough!!
 			else
 				goto retry;
 		}
+		if (P_MobjWasRemoved(mo))
+			return;
 		success = true;
 	} while(tmxmove || tmymove);
 }

src/p_mobj.c

@@ -2118,7 +2118,7 @@ void P_RingXYMovement(mobj_t *mo)
 	I_Assert(mo != NULL);
 	I_Assert(!P_MobjWasRemoved(mo));
 
-	if (!P_SceneryTryMove(mo, mo->x + mo->momx, mo->y + mo->momy))
+	if (!P_SceneryTryMove(mo, mo->x + mo->momx, mo->y + mo->momy) && !P_MobjWasRemoved(mo))
 		P_SlideMove(mo);
 }
 
@@ -2132,8 +2132,10 @@ void P_SceneryXYMovement(mobj_t *mo)
 	oldx = mo->x;
 	oldy = mo->y;
 
-	if (!P_SceneryTryMove(mo, mo->x + mo->momx, mo->y + mo->momy))
+	if (!P_SceneryTryMove(mo, mo->x + mo->momx, mo->y + mo->momy) && !P_MobjWasRemoved(mo))
 		P_SlideMove(mo);
+	if (P_MobjWasRemoved(mo))
+		return;
 
 	if ((!(mo->eflags & MFE_VERTICALFLIP) && mo->z > mo->floorz) || (mo->eflags & MFE_VERTICALFLIP && mo->z+mo->height < mo->ceilingz))
 		return; // no friction when airborne
@@ -3914,6 +3916,8 @@ static void P_PlayerMobjThinker(mobj_t *mobj)
 	}
 	else
 		P_TryMove(mobj, mobj->x, mobj->y, true);
+	if (P_MobjWasRemoved(mobj))
+		return;
 
 	P_CheckCrumblingPlatforms(mobj);
 
@@ -4708,6 +4712,8 @@ static void P_Boss4PinchSpikeballs(mobj_t *mobj, angle_t angle, fixed_t dz)
 		{
 			seg->z = bz + (dz*(9-s));
 			P_TryMove(seg, workx + (dx*s), worky + (dy*s), true);
+			if (P_MobjWasRemoved(seg))
+				return;
 		}
 		angle += ANGLE_MAX/3;
 	}
@@ -4945,6 +4951,8 @@ static void P_Boss4Thinker(mobj_t *mobj)
 				(mobj->spawnpoint->x<<FRACBITS) - P_ReturnThrustX(mobj, mobj->angle, mobj->movefactor),
 				(mobj->spawnpoint->y<<FRACBITS) - P_ReturnThrustY(mobj, mobj->angle, mobj->movefactor),
 				true);
+		if (P_MobjWasRemoved(mobj))
+			return;
 
 		P_Boss4PinchSpikeballs(mobj, FixedAngle(mobj->movecount), mobj->z - mobj->watertop - mobjinfo[MT_EGGMOBILE4_MACE].height - mobj->height/2);
 
@@ -5514,6 +5522,8 @@ static void P_Boss9Thinker(mobj_t *mobj)
 	{
 		P_InstaThrust(mobj, mobj->angle, -4*FRACUNIT);
 		P_TryMove(mobj, mobj->x+mobj->momx, mobj->y+mobj->momy, true);
+		if (P_MobjWasRemoved(mobj))
+			return;
 		mobj->momz -= gravity;
 		if (mobj->z < mobj->watertop || mobj->z < (mobj->floorz + 16*FRACUNIT))
 		{
@@ -5862,6 +5872,8 @@ static void P_Boss9Thinker(mobj_t *mobj)
 					P_InstaThrust(mobj, mobj->angle, 30*FRACUNIT);
 				if (!P_TryMove(mobj, mobj->x+mobj->momx, mobj->y+mobj->momy, true))
 				{ // Hit a wall? Find a direction to bounce
+					if (P_MobjWasRemoved(mobj))
+						return;
 					mobj->threshold--;
 					if (!mobj->threshold) { // failed bounce!
 						S_StartSound(mobj, sfx_mspogo);
@@ -5902,6 +5914,8 @@ static void P_Boss9Thinker(mobj_t *mobj)
 			P_InstaThrust(mobj, mobj->angle, -speed);
 			while (!P_TryMove(mobj, mobj->x+mobj->momx, mobj->y+mobj->momy, true) && tries++ < 16)
 			{
+				if (P_MobjWasRemoved(mobj))
+					return;
 				S_StartSound(mobj, sfx_mspogo);
 				P_BounceMove(mobj);
 				mobj->angle = R_PointToAngle2(mobj->momx, mobj->momy,0,0);
@@ -7501,6 +7515,8 @@ static void P_RosySceneryThink(mobj_t *mobj)
 			fixed_t x = mobj->x, y = mobj->y, z = mobj->z;
 			angle_t angletoplayer = R_PointToAngle2(x, y, mobj->target->x, mobj->target->y);
 			boolean allowed = P_TryMove(mobj, mobj->target->x, mobj->target->y, false);
+			if (P_MobjWasRemoved(mobj))
+				return;
 
 			P_UnsetThingPosition(mobj);
 			mobj->x = x;
@@ -8064,7 +8080,8 @@ static void P_MobjSceneryThink(mobj_t *mobj)
 		break;
 	}
 
-	P_SceneryThinker(mobj);
+	if (!P_MobjWasRemoved(mobj))
+		P_SceneryThinker(mobj);
 }
 
 static boolean P_MobjPushableThink(mobj_t *mobj)
@@ -10423,6 +10440,8 @@ void P_MobjThinker(mobj_t *mobj)
 		|| mobj->type == MT_CANNONBALLDECOR
 		|| mobj->type == MT_FALLINGROCK) {
 		P_TryMove(mobj, mobj->x, mobj->y, true); // Sets mo->standingslope correctly
+		if (P_MobjWasRemoved(mobj))
+			return;
 		//if (mobj->standingslope) CONS_Printf("slope physics on mobj\n");
 		P_ButteredSlope(mobj);
 	}
@@ -10524,6 +10543,8 @@ void P_PushableThinker(mobj_t *mobj)
 	// it has to be pushable RIGHT NOW for this part to happen
 	if (mobj->flags & MF_PUSHABLE && !(mobj->momx || mobj->momy))
 		P_TryMove(mobj, mobj->x, mobj->y, true);
+	if (P_MobjWasRemoved(mobj))
+		return;
 
 	if (mobj->type == MT_MINECART && mobj->health)
 	{
@@ -14017,7 +14038,8 @@ boolean P_CheckMissileSpawn(mobj_t *th)
 
 	if (!P_TryMove(th, th->x, th->y, true))
 	{
-		P_ExplodeMissile(th);
+		if (!P_MobjWasRemoved(th))
+			P_ExplodeMissile(th);
 		return false;
 	}
 	return true;

src/p_tick.c

@@ -844,7 +844,7 @@ void P_Ticker(boolean run)
 		if (quake.time)
 			--quake.time;
 
-		if (metalplayback)
+		if (!P_MobjWasRemoved(metalplayback))
 			G_ReadMetalTic(metalplayback);
 		if (metalrecording)
 			G_WriteMetalTic(players[consoleplayer].mo);

src/p_user.c

@@ -11101,7 +11101,8 @@ static void P_MinecartThink(player_t *player)
 	fa = (minecart->angle >> ANGLETOFINESHIFT) & FINEMASK;
 	if (!P_TryMove(minecart, minecart->x + FINECOSINE(fa), minecart->y + FINESINE(fa), true))
 	{
-		P_KillMobj(minecart, NULL, NULL, 0);
+		if (!P_MobjWasRemoved(minecart))
+			P_KillMobj(minecart, NULL, NULL, 0);
 		return;
 	}
 
@@ -12455,7 +12456,7 @@ void P_PlayerThink(player_t *player)
 			player->texttimer = 4*TICRATE;
 			player->textvar = 2; // GET n RINGS!
 
-			if (player->capsule && player->capsule->health != player->capsule->spawnpoint->angle)
+			if (!P_MobjWasRemoved(player->capsule) && player->capsule->health != player->capsule->spawnpoint->angle)
 				player->textvar++; // GET n MORE RINGS!
 		}
 	}

src/r_main.c

@@ -1363,7 +1363,7 @@ void R_SkyboxFrame(player_t *player)
 			newview->z += campos.z * -mh->skybox_scalez;
 	}
 
-	if (r_viewmobj->subsector)
+	if (!P_MobjWasRemoved(r_viewmobj) && r_viewmobj->subsector)
 		newview->sector = r_viewmobj->subsector->sector;
 	else
 		newview->sector = R_PointInSubsector(newview->x, newview->y)->sector;

src/st_stuff.c

@@ -1926,7 +1926,7 @@ static void ST_drawNiGHTSHUD(void)
 		total_ringcount = stplyr->spheres;
 	}
 
-	if (stplyr->capsule)
+	if (!P_MobjWasRemoved(stplyr->capsule))
 	{
 		INT32 amount;
 		const INT32 length = 88;